ci: Remove the Windows CI workflow

[azeey]

Summary

We are now using pixi on Jenkins so this is no longer needed.

Checklist

• Signed all commits for DCO
• Added a screen capture or video to the PR description that demonstrates the fix (as needed)
• Added tests
• Updated documentation (as needed)
• Updated migration guide (as needed)
• Consider updating Python bindings (if the library has them)
• codecheck passed (See contributing)
• All tests passed (See test coverage)
• Updated Bazel files (if adding new files). Created an issue otherwise.
• While waiting for a review on your PR, please help review another open pull request to support the maintainers
• Was GenAI used to generate this PR? If so, make sure to add "Generated-by" to your commits. (See this policy for more info.)

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[iche033]

do we still need #1052?

[azeey]

@Mergifyio backport gz-rendering10 gz-rendering9

[mergify]

backport gz-rendering10 gz-rendering9

✅ Backports have been created

Details

• #1240 ci: Remove the Windows CI workflow (backport #1239) has been created for branch gz-rendering10 but encountered conflicts

Cherry-pick of 8d7abc5 has failed:

On branch mergify/bp/gz-rendering10/pr-1239
Your branch is up to date with 'origin/gz-rendering10'.

You are currently cherry-picking commit 8d7abc5f.
  (fix conflicts and run "git cherry-pick --continue")
  (use "git cherry-pick --skip" to skip this patch)
  (use "git cherry-pick --abort" to cancel the cherry-pick operation)

Unmerged paths:
  (use "git add/rm <file>..." as appropriate to mark resolution)
	deleted by them: .github/workflows/windows.yaml

no changes added to commit (use "git add" and/or "git commit -a")

To fix up this pull request, you can check it out locally. See documentation: https://docs.github.com/en/pull-requests/collaborating-with-pull-requests/reviewing-changes-in-pull-requests/checking-out-pull-requests-locally

• #1241 ci: Remove the Windows CI workflow (backport #1239) has been created for branch gz-rendering9 but encountered conflicts

Cherry-pick of 8d7abc5 has failed:

On branch mergify/bp/gz-rendering9/pr-1239
Your branch is up to date with 'origin/gz-rendering9'.

You are currently cherry-picking commit 8d7abc5f.
  (fix conflicts and run "git cherry-pick --continue")
  (use "git cherry-pick --skip" to skip this patch)
  (use "git cherry-pick --abort" to cancel the cherry-pick operation)

Unmerged paths:
  (use "git add/rm <file>..." as appropriate to mark resolution)
	deleted by them: .github/workflows/windows.yaml

no changes added to commit (use "git add" and/or "git commit -a")

To fix up this pull request, you can check it out locally. See documentation: https://docs.github.com/en/pull-requests/collaborating-with-pull-requests/reviewing-changes-in-pull-requests/checking-out-pull-requests-locally