Allow vector-0.12.2, skip lens tests
Allow vector-0.12.2, skip lens tests

This implements the plan set out in
https://github.com/commercialhaskell/stackage/issues/5851#issuecomment-770405905.

Fixes #5851.

mrkkrp/stackage,Daniel-Diaz/stackage,michalkonecny/stackage,soenkehahn/stackage,simonmichael/stackage,iand675/stackage,fpco/stackage,jonschoning/stackage