Fix: rm usage of undefined function "remove"

[jinyus]

It looks like the docs referenced a function that has been deprecated/removed. I replaced it with remove_file from std.fs.path.

inko/docs/source/getting-started/error-handling.md

Line 224 in 8f5ad1e

let _ = remove(file.path)

[yorickpeterse]

@jinyus You're right, I forget to update that when the various file methods were moved around a while back. Thanks 😃

[yorickpeterse]

I merged this into 9e4f82b and added the changelog tag. Thanks! 🎉