Installing virtualbmc system-wide on CentOS 8 fails with:
ModuleNotFoundError: No module named 'setuptools_rust'
This error appeared following the release of cryptography 3.4, which now
includes Rust code. It can be installed without Rust using a Python
wheel, but only with more recent pip than version 9.0.3 available as RPM
on CentOS 8. The cryptography bug report [1] recommends pip>=19.1.1.
Also ignore PyYAML when installing system-wide to avoid conflicts with
an existing RPM package installation.
[1] https://github.com/pyca/cryptography/issues/5753
Change-Id: Ibd61e090611b3b7a7e0670c854362b512454bf3c
Story: 2008607
Task: 41788
f34bb772a0