codesign: do not sign stuff that is inside the bundled python

bundled framework are signed as a 'framework'..
it does not seems like we should sign random piece of it while
attempting to sign the App itself

Change-Id: Ia9ea34f5ba484e4a15337aa4edabd86e3b5fe406
Reviewed-on: https://gerrit.libreoffice.org/7387
Reviewed-by: Christian Lohmaier <lohmaier+LibreOffice@googlemail.com>
Tested-by: Christian Lohmaier <lohmaier+LibreOffice@googlemail.com>