Use async io where possible to improve runtime performance

[netomi]

This PR fixes #162 .

Things that this PR will modify:

• use aiohttp whereever appropriate to improve performance
• cleanups of existing code where appropriate (e.g. get_pypi_data_from_purl which returned duplicate data for each package)

[TG1999]

@netomi thanks! please check the errors in the CI and also do not forget to regen the tests just in case dependencies in tests have been updated https://github.com/nexB/python-inspector#testing

[netomi]

There are a couple of things that I still need to fix, but the failing CI runs are unrelated to this PR afaict. They also exist for other PRs and look like that the setup is broken.

[TG1999]

@netomi please rebase your PR with latest main, tests are fixed in this PR https://github.com/nexB/python-inspector/pull/165

[netomi]

ok so there are some unit test failure that I need to address. Most of them are from the fact that python-inspector returned duplicate package entries in its result up to now, which I fixed, so the expected test results need to be adjusted to take this change into account.

[netomi]

I could fix most tests (weird thing is that 4 tests fail locally when run in pycharm, but work on the command line so that might be a pycharm problem), there are some weird test failures on macos and windows only. Do you have any idea about that?

[netomi]

still need to take a look at etc/scripts if the there also need to be adjustments after the changes.

[pombredanne]

@netomi BTW, do not bother with the etc/scripts ... these come from the shared skeleton repo at https://github.com/nexB/skeleton and should not be of concern for you.

[sschuberth]

Can this be moved forward, please? 😬

[TG1999]

@sschuberth tests are falling, tests needs to be regen