Htgettoken

- Add BuildRequires python3-devel to generate correct Python metadata.
- Remove explicit Requires for python dependencies, rely on Python metadata.
- Always build with wheels.
- Remove Python root logger configuration.

- Fix broken httokendecode symlink.
- Use python wheels to build/install on el9. It didn't work on el8 so the use of wheels was removed at the last minute before the 2.0-1 release (without removing it from the changelog like it should have).

- Fix htdecodetoken to work with token files that do not end in a newline.
- Support args in htgettoken.main() Python entry point.

- Replace use of m2crypto and pyOpenSSL with urllib3
- Replace use of pykerberos with gssapi
- Use standard Requires for Python modules instead of PyInstaller
- Add --vaultcertname option to specify an alternative certificate name. That used to be an additional optional meaning of the --vaultalias option, but urllib3 requires only one name to match.
- Add setuptools build infrastructure
- Refactor htgettoken script into module with entry point. This enables invoking htgettoken as `htgettoken.main()` from Python.
- Use wheels to build/install Python package, which simplified the entry points and improves (slightly) the metadata
- Fix the httokensh background process's check for its parent process. That is only a backup in case only the parent process is hard-killed, because normally the parent process kills the background process when the parent exits.
- Use newer `sts` secrets API for token exchanges.
- Fix the `-o`/`--outfile` option to work with relative paths.
- Change the `--nobearertoken` option to always get and save a vault token.

This release does not change the main htgettoken package, it only changes make-downloads to avoid using --no-deps when it can. That re-enables building without network access for example on OSG koji.

- Suppress python warnings in order to avoid CryptographyDeprecationWarning about python3.6 being deprecated.