fix compile_pip_requirements on windows

[jheaff1]

PR Checklist

Please check if your PR fulfills the following requirements:

• Tests for the changes have been added (for bug fixes / features)
• Docs have been added / updated (for bug fixes / features)

PR Type

What kind of change does this PR introduce?

• Bugfix
• Feature (please, look at the "Scope of the project" section in the README.md file)
• Code style update (formatting, local variables)
• Refactoring (no functional changes, no api changes)
• Build related changes
• CI related changes
• Documentation content changes
• Other... Please describe:

What is the current behavior?

PR #529 updated click to a version which depends on colorama on Windows. This broke the generation of a requirements.txt lock file using the compile_pip_requirements rule on windows.
Issue Number: #529

What is the new behavior?

The generation of a requirements.txt lock file using the compile_pip_requirements rule on windows now works

Does this PR introduce a breaking change?

• Yes
• No

Other information

[UebelAndre]

Now that rules_python runs tests on Windows runners in CI (#585), I'm surprised this wasn't caught then. I thought compile_pip_requirements was run as part of the @rules_python//examples:pip_install_example integration test:
https://github.com/bazelbuild/rules_python/blob/0.6.0/examples/pip_install/BUILD#L69-L73

Do you know why this might not be caught by that test and if something can be done to improve the test coverage for the rule?

[jheaff1]

Now that rules_python runs tests on Windows runners in CI (#585), I'm surprised this wasn't caught then. I thought compile_pip_requirements was run as part of the @rules_python//examples:pip_install_example integration test: https://github.com/bazelbuild/rules_python/blob/0.6.0/examples/pip_install/BUILD#L69-L73

Do you know why this might not be caught by that test and if something can be done to improve the test coverage for the rule?

It seems that test_runner.py did not detect failing tests. Please see #597

[UebelAndre]

It seems that test_runner.py did not detect failing tests. Please see #597

Most unfortunate. Though, having tested these changes on both macos and windows, I think they're good. Both platforms work and I think it'd be good to have this change while the test runner issues are fixed separately.

Though, I'm not a maintainer so my opinion has little value here 😅

[alexeagle]

thanks!