Github workflow: Fix python link error on macOS

 Homebrew recently shifted to python3.12 as the default python on some
 but not all versions of macOS.  This fix resolves a package linking
 issue experienced when installing python based packages.

.github/workflows/buildmaster.yml

@@ -100,13 +100,17 @@ jobs:
         env:
           OS_VERS: ${{ matrix.os }}
         run: |
-          brew update
+          ${PKGMGR_CMD} update
+          ${PKGMGR_CMD} unlink python
+          ${PKGMGR_CMG} brew install [email protected]
+          ${PKGMGR_CMD} link --overwrite [email protected]
           ${PKGMGR_CMD} install pkg-config ccache qt5 nasm libsamplerate taglib\
             lzo libcec libbluray libass libhdhomerun dav1d x264 x265 libvpx \
             openssl sound-touch lame freetype libass libiconv libxml2 libzip \
             XviD zlib pyenv-virtualenv python-lxml  python-requests \
             python-setuptools
           ${PKGMGR_CMD} link qt5 --force
+          ${PKGMGR_CMD} link python --force
           # macos-14 updated the linker and needs to be run in "classic" mode
           case $OS_VERS in
             macos-14)