Bump FreeBSD to 13.2

[tim-dlang]

The DMD nightly build for FreeBSD fails since two weeks, because the old version is not available anymore. As a result the nightly builds for other platforms are also not uploaded.

This increases the versions for FreeBSD the same as in dlang/dmd#15979, but I have not tested it.

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[PetarKirov]

Thank you, @tim-dlang!