Drop questionable CLT advice

If an outdated Xcode is installed, it really needs to be updated if
possible. Otherwise things that depend on Xcode at build time will have
that dependency satisfied, but will fail to compile. The CLT is enough
if it is installed by itself, in which case Xcode dependencies will not
be satisfied.
sfml: added head

Closes #33395.
sfml: update 2.1 bottle.