additional edge cases tests for path.rs 🧪

[GrantBirki]

This pull request adds a few new edge case tests to the std::path module. The new tests cover scenarios such as paths with only separators, non-ASCII and Unicode characters, embedded new lines, etc. Each new test is documented with some helpful in-line comments as well.

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[GrantBirki]

It appears that mingw-check-tidy failed, but I am not sure how to correct it. Perhaps its a linter of some sort?

[ChaiTRex]

It appears that mingw-check-tidy failed, but I am not sure how to correct it. Perhaps its a linter of some sort?

mingw-check also failed. Click on CI / PR - mingw-check (pull_request) and see the compiler errors toward the bottom.

[ChaiTRex]

It looks as if OsStrExt and OsStringExt have different methods on Windows than other platforms.

[workingjubilee]

Yes, please fix the tests to only use functions from OsStr and OsString OR cfg the tests.

[GrantBirki]

@ChrisDenton I went ahead and removed a few of the tests that I added which feel rather superfluous now after reading your comments. This slims down the PR to really just be three new unit tests.