Revert "install_pmbootstrap.sh: use 2.3.x branch (MR 6)"

pmbootstrap master is now good enough to use as default in CI.

See pmbootstrap#2396 (closed)

This reverts commit 755b5064.

requested review from @calebccff

approved this merge request

Probably easiest to ship it and see what repos break... pmaports is the important one and that's done already.

added 1 commit

• 666df6d1 - Revert "install_pmbootstrap.sh: use 2.3.x branch (MR 6)" (MR 8)

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enabled an automatic merge when all merge checks for 666df6d1 pass

merged