hooks/pre-pkg/06-verify-python-deps: support alternative packages

[tornaria]

Testing the changes

• I tested the changes in this PR: YES

[tornaria]

This is needed for python3-jupyter_nbconvert which depends on python3-mistune, but python3-mistune2 also provides py:mistune.

[tornaria]

Example run (I removed a few deps from python3-jupyter_nbconvert to show the output):

=> python3-jupyter_nbconvert-7.16.6_1: running pre-pkg hook: 06-verify-python-deps ...
   PYTHON: py3:beautifulsoup4 <-> python3-BeautifulSoup4
   PYTHON: py3:bleach <-> python3-bleach
   PYTHON: py3:defusedxml <-> python3-defusedxml
   PYTHON: py3:jinja2 <-> python3-Jinja2
   PYTHON: py3:jupyter-core <-> python3-jupyter_core
   PYTHON: py3:jupyterlab-pygments <-> python3-jupyterlab_pygments
   PYTHON: py3:markupsafe <-> python3-MarkupSafe NOT IN depends PLEASE FIX!
   PYTHON: py3:mistune <-> (python3-mistune OR python3-mistune2) NOT IN depends PLEASE FIX!
   PYTHON: py3:nbclient <-> python3-nbclient NOT IN depends PLEASE FIX!
   PYTHON: py3:nbformat <-> python3-jupyter_nbformat
   PYTHON: py3:packaging <-> python3-packaging
   PYTHON: py3:pandocfilters <-> python3-pandocfilters
   PYTHON: py3:pygments <-> python3-Pygments
   PYTHON: py3:traitlets <-> python3-traitlets
=> python3-jupyter_nbconvert-7.16.6_1: missing dependencies detected!
=> python3-jupyter_nbconvert-7.16.6_1: please add these packages to depends: (python3-mistune OR python3-mistune2) python3-MarkupSafe python3-nbclient

For packages with only one provider, the output should be identical as before.

For packages with multiple providers, we use parenthesis to make the final suggestion easier to read, for instance (python3-mistune OR python3-mistune2).