Added integration test for testing nuances of pip_repository macros

[UebelAndre]

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?

#598 is too big to review so this PR breaks out a component of it.

Issue Number: N/A

What is the new behavior?

The tests in the pip_parse and pip_install examples are not cross platform since sphinx has differing dependency graphs between windows and linux/macos. This introduces a new integration test which continues to test important functionality on linux and macos until a cross platform solution is found.

Does this PR introduce a breaking change?

• Yes
• No

Other information

[UebelAndre]

@f0rmiga Thanks for the review! If this gets merged then I can open one more to finally fix Windows CI 😄