Currently a few packages are installed without it, pulling in undesired
updates (e.g. cryptography 2.8 on stable/steain). This change fixes it.
The --upgrade and --force-reinstall flags are removed from all pip calls
since they're not compatible with using upper-constraints.
The explicit installation of pyOpenSSL is removed, >= 18.0 is anyway
used by Rocky and newer. A few explicit usages of -c argument are
also removed in favour of the implicit handling in pip_install.yml.
Change-Id: Ic776cb2ec0779c9b324e94bf387ee4f3f857cd72