devel/py-breathe: repair havoc wreaked by bc7ed2ccd62e

bc7ed2ccd62 was insufficiently made, so I will credit as:

Broken by: vishwin@
PR: 270510

I herewith have recorded that this was in violation of
long-standing best practice that we give maintainers
ports affected by sweeping changes such as the one in bc7ed...
sufficient heads-up so this can be properly reviewed
before inflicting the damage.

vishwin@ has been around the project for long enough that
he should know this, and I observe that there is a strong
imbalance of how this person opposes certain advances in
the project, all the while applying different standards when
bringing "his own" changes forward.

Also, deprecating something via CHANGES without a clear
alternative path forward is insufficient. Don't tell
what your co-committers should not do without showing the
proper way forward.

For the record, this is damaging and such behaviors
must change, urgently.

To fix py-breathe:

• Re-add setuptools as a dependency, and duly note that

the CHANGES entry in the mentioned Git commit is utterly and
completely insufficient WRT future directions.

• Bump PORTREVISION to trigger rebuild attempts.

Reported by: antoine@ (thank you very much for this suggestion)
Tested by: diizzy@
Fixes: bc7ed2ccd62e - main - python.mk: remove setuptools from RUN_DEPENDS