[3.12] gh-117711: Only check for 'test/wheeldata' when it's actually used (GH-117712...

[3.12] gh-117711: Only check for 'test/wheeldata' when it's actually used (GH-117712) (#117749)

gh-117711: Only check for 'test/wheeldata' when it's actually used (GH-117712)

It's possible to build Python with option `--with-wheel-pkg-dir`
pointing to a custom wheel directory. Don't include the directory in the test
set if the wheels are used from a different location.

(cherry picked from commit d4963871b03cc76fe7d9648d022d12007585beae)

Co-authored-by: Karolina Surma <33810531+befeleme@users.noreply.github.com>
Co-authored-by: Miro Hrončok <miro@hroncok.cz>