Update CI handling of pyenv IT interpreters. (#1549)
Update CI handling of pyenv IT interpreters. (#1549)

In #1545 I missed updating CI handling. Although this led to no errors,
the cache key bump at least, was needed to save cache space and purge
the old 3.8 pyenv interpreter stored there.
jsirois/pex,jsirois/pex,pantsbuild/pex,pantsbuild/pex