Update pip to v22.1

[kmecpp]

The current version (22.0.4) doesn't have support for this flag pypa/pip#10990 / pypa/pip#11035

[tianon]

The intent of the pinning changes we did was to allow Python upstream to determine which version of pip we're installing (so that we're consistent with a vanilla install of Python since there are so many opinions on specifically which version of pip we should provide).

It does appear that we're finally to a place where the version of pip in every supported version of Python is higher than what we were pinning our minimum to (for backwards compatibility with our previous images only), so we should probably remove all the "minimum pip version" code from that versions.sh file instead.

If you want or need a newer pip in your own images, I'd suggest updating it early in your Dockerfile.