Avoid calling sudo in install_venv_common.py.

Updates our common venv installation routine so that it no longer
attempts to automatically install missing RPM packages via sudo
and instead just prints an error message and dies.

The primary motivation here was to avoid sudo altogether since
some people would rather not have the test suite run these sorts
of systems admin commands for them.

Change-Id: I350e5421a4dd3094217270d39547acaea0aeda3b
Merge "Avoid calling sudo in install_venv_common.py."