Improve issue and PR templates

[rly]

Motivation

Fix #1003. I also simplified the PR template to reduce the number of checkboxes and text.

I also reordered the Python versions in the issue template to newer first, and I changed the order of OS's to Mac first since that is currently used by all of the core HDMF developers.

How to test the behavior?

Need to merge this PR to see the changes.

Checklist

• Did you update CHANGELOG.md with your changes?
• Have you checked our Contributing document?
• Have you ensured the PR clearly describes the problem and the solution?
• Is your contribution compliant with our coding style? This can be checked running ruff from the source directory.
• Have you checked to ensure that there aren't other open Pull Requests for the same change?
• Have you included the relevant issue number using "Fix #XXX" notation where XXX is the issue number? By including "Fix #XXX" you allow GitHub to close issue #XXX when the PR is merged.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 88.65%. Comparing base (1d7fd83) to head (0436e98).
Report is 92 commits behind head on dev.

Additional details and impacted files

@@           Coverage Diff           @@
##              dev    #1004   +/-   ##
=======================================
  Coverage   88.65%   88.65%           
=======================================
  Files          45       45           
  Lines        9458     9458           
  Branches     2691     2691           
=======================================
  Hits         8385     8385           
  Misses        757      757           
  Partials      316      316           

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