fix: pypi parse_simpleapi_html.bzl is robust to metadata containing ">" sign

[mihaidusmanu]

This PR modifies the logic for finding the end of the of the
tag metadata attributes in the pypi parse_simpleapi_html function.

This was discovered after investigation of the following error:

Error in repository_rule: invalid user-provided repo name 'pypi_311_=2_7,!=3_0_*,!=3_1_*,!=3_2_*">six_py2_none_any_8abb2f1d': valid names may contain only A-Z, a-z, 0-9, '-', '_', '.', and must start with a letter

which was traced back to the to a data-requires-python attribute containing a > sign (instead of >) in the Azure Artifacts pypi feed, e.g.:
<a href="https://microsoft.pkgs.visualstudio.com/REDACTED_URL/six-1.16.0-py2.py3-none-any.whl#sha256=8abb2f1d86890a2dfb989f9a77cfcfd3e47c2a354b01111771326f8aa26e0254" data-requires-python=">=2.7,!=3.0.*,!=3.1.*,!=3.2.*">six-1.16.0-py2.py3-none-any.whl</a><br/>

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[aignas]

@mihaidusmanu, could you please rebase on latest main, add a line in CHANGELOG.md and also accept the Google's CLA please?

The PR description would become a commit message, so feel free to clean it up a little, so that it looks better when reading git log. :)

Thanks for the contribution!

[mihaidusmanu]

Hello @aignas - I just signed the CLA, updated the changelog and also tried to update the PR description.

Regarding rebasing on latest main, I believe it is already up to date (?)

[aignas]

I simplified the code using rpartition instead of using for loop and finding quotes. It is still passing the tests you have added. Thanks a lot by adding more tests!