* Revert "Revert "Use PyCapsule for internal datetime functions" (#51951)"

This reverts commit 8487b2e2.

* Revert "Revert "Re-enable parallel builds in CI" (#51952)"

This reverts commit c8ea34c6.

* Revert "Revert "CI: parallel build follow up" (#51984)"

This reverts commit 93b5135f.