Add MiniMagick v5.0 (#629)

Since MiniMagick v5.0 has been released, add types.

https://github.com/minimagick/minimagick/tree/v5.0.1

The README includes the following usage example,
but methods such as resize and format do not exist and there are hacked by method_missing.

```ruby
image = MiniMagick::Image.open("input.jpg")
image.path
image.resize "100x100"
image.format "png"
image.write "output.png"
```

Since it is not possible to determine whether a method can be used or not depending on the version of ImageMagick being used,
methods that are hacked with method_missing are not defined in the collection.

gems/mini_magick/5.0/_test/metadata.yaml

@@ -0,0 +1,4 @@
+# If the test needs gem's RBS files, declare them here.
+#
+# additional_gems:
+#   - GEM_NAME

gems/mini_magick/5.0/_test/readme.rb

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+require "mini_magick"
+
+## Usage
+
+image = MiniMagick::Image.open("input.jpg")
+image.path # steep:ignore
+image.resize "100x100" # steep:ignore
+image.format "png" # steep:ignore
+image.write "output.png" # steep:ignore
+
+image = MiniMagick::Image.open("http://example.com/image.jpg")
+image.contrast # steep:ignore
+image.write("from_internets.jpg")
+
+image = MiniMagick::Image.new("input.jpg")
+image.path  #=> "input.jpg"
+image.resize "100x100" # steep:ignore
+
+### Combine options
+
+image.combine_options do |b|
+  b.resize "250x200>" # steep:ignore
+  b.rotate "-90" # steep:ignore
+  b.flip # steep:ignore
+end # the command gets executed
+
+image = MiniMagick::Image.new("input.jpg") do |b|
+  b.resize "250x200>" # steep:ignore
+  b.rotate "-90" # steep:ignore
+  b.flip # steep:ignore
+end # the command gets executed
+
+### Attributes
+
+image.type        #=> "JPEG"
+image.width       #=> 250
+image.height      #=> 300
+image.dimensions  #=> [250, 300]
+image.size        #=> 3451 (in bytes)
+image.colorspace  #=> "DirectClass sRGB"
+image.exif        #=> {"DateTimeOriginal" => "2013:09:04 08:03:39", ...}
+image.resolution  #=> [75, 75]
+image.signature   #=> "60a7848c4ca6e36b8e2c5dea632ecdc29e9637791d2c59ebf7a54c0c6a74ef7e"
+
+image["%[gamma]"] # "0.9"
+
+image.data
+
+### Pixels
+
+image = MiniMagick::Image.open("image.jpg")
+pixels = image.get_pixels
+# pixels[3][2][1] # the green channel value from the 4th-row, 3rd-column pixel
+
+image = MiniMagick::Image.open("image.jpg")
+image.crop "20x30+10+5" # steep:ignore
+image.colorspace "Gray" # steep:ignore
+pixels = image.get_pixels
+
+### Pixels To Image
+
+image = MiniMagick::Image.open('/Users/rabin/input.jpg')
+pixels = image.get_pixels
+depth = 8
+dimension = [image.width, image.height]
+map = 'rgb'
+image = MiniMagick::Image.get_image_from_pixels(pixels, dimension, map, depth ,'jpg')
+image.write('/Users/rabin/output.jpg')
+
+### Configuration
+
+MiniMagick.configure do |config|
+  config.timeout = nil # number of seconds IM commands may take
+  config.errors = true # raise errors non nonzero exit status
+  config.warnings = true # forward warnings to standard error
+  config.tmpdir = Dir.tmpdir # alternative directory for tempfiles
+  config.logger = Logger.new($stdout) # where to log IM commands
+  config.cli_prefix = nil # add prefix to all IM commands
+end
+
+### Composite
+
+first_image  = MiniMagick::Image.new("first.jpg")
+second_image = MiniMagick::Image.new("second.jpg")
+result = first_image.composite(second_image) do |c|
+  c.compose "Over" # steep:ignore
+  c.geometry "+20+20" # steep:ignore
+end
+result.write "output.jpg"
+
+### Layers/Frames/Pages
+
+gif = MiniMagick::Image.open('/Users/rabin/input.gif')
+pdf = MiniMagick::Image.open('/Users/rabin/input.pdf')
+psd = MiniMagick::Image.open('/Users/rabin/input.psd')
+gif.frames #=> [...]
+pdf.pages  #=> [...]
+psd.layers #=> [...]
+
+gif.frames.each_with_index do |frame, idx|
+  frame.write("frame#{idx}.jpg")
+end
+
+### Image validation
+
+image.valid?
+image.validate! # raises MiniMagick::Invalid if image is invalid
+
+### Logging
+
+MiniMagick.logger.level = Logger::DEBUG
+
+## Tools
+
+MiniMagick.convert do |convert|
+  convert << "input.jpg"
+  convert.resize("100x100") # steep:ignore
+  convert.negate # steep:ignore
+  convert << "output.jpg"
+end
+
+convert = MiniMagick.convert
+convert << "input.jpg"
+convert.resize("100x100") # steep:ignore
+convert.negate # steep:ignore
+convert << "output.jpg"
+convert.call
+
+### Appending
+
+MiniMagick.convert do |convert|
+  convert << "input.jpg"
+  convert.merge! ["-resize", "500x500", "-negate"]
+  convert << "output.jpg"
+end
+
+### "Plus" options
+
+MiniMagick.convert do |convert|
+  convert << "input.jpg"
+  convert.+
+  # convert.repage.+
+  # convert.distort.+("Perspective", "more args")
+end
+
+### Stacks
+
+MiniMagick.convert do |convert|
+  convert << "wand.gif"
+
+  convert.stack do |stack|
+    stack << "wand.gif"
+    stack.rotate(30) # steep:ignore
+    stack.foo("bar", "baz") # steep:ignore
+  end
+  # or
+  convert.stack("wand.gif", { rotate: 30, foo: ["bar", "baz"] })
+
+  convert << "images.gif"
+end
+
+### STDIN and STDOUT
+
+identify = MiniMagick.identify
+identify.stdin # alias for "-"
+identify.call(stdin: "")
+
+content = MiniMagick.convert do |convert|
+  convert << "input.jpg"
+  convert.auto_orient # steep:ignore
+  convert.stdout # alias for "-"
+end
+
+## Configuring
+
+### GraphicsMagick
+
+MiniMagick.configure do |config|
+  config.cli_prefix = "gm"
+end
+
+### Changing temporary directory
+
+MiniMagick.configure do |config|
+  config.tmpdir = File.join(Dir.tmpdir, "/my/new/tmp_dir")
+end
+
+### Avoiding raising errors
+
+MiniMagick.configure do |config|
+  config.errors = false
+end
+
+MiniMagick.identify(errors: false) do |b|
+  b.help # steep:ignore
+end

gems/mini_magick/5.0/_test/test.rb

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+require "mini_magick"
+
+MiniMagick::Error
+MiniMagick::Invalid
+MiniMagick::TimeoutError
+
+MiniMagick.imagemagick7?
+MiniMagick.cli_version
+
+MiniMagick.version == "5.0"
+
+MiniMagick::Tool.new("mogrify", foo: "FOO") do |mogrify|
+  mogrify.resize "100x100" # steep:ignore
+  mogrify << 1
+  mogrify.merge!(["-foo", 1, nil])
+  mogrify.+("Perspective", "0,0,4,5 89,0,45,46")
+  mogrify.stack do |stack|
+    stack << "wand.gif"
+  end
+  mogrify.stdin
+  mogrify.stdout
+  mogrify.xc
+  mogrify.canvas("khaki")
+  mogrify.executable
+  mogrify.call
+end
+
+mogrify = MiniMagick::Tool.new("mogrify", foo: "FOO")
+mogrify.call

gems/mini_magick/5.0/manifest.yaml

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+dependencies:
+  - name: logger
+  - name: pathname
+  - name: tempfile
+  - name: tmpdir
+  - name: uri