testing/clementine: new aport (and some dependencies)

This MR adds the following packages:

• testing/liblastfm-qt
• testing/libmygpo-qt
• testing/projectm
• testing/clementine

Currently set to draft as the build fails; the issue is that the /tmp directory permissions change from drwxrwxrwt to drwxr-xr-x somewhere between ">>> projectm-pulseaudio-doc*: Preparing subpackage projectm-pulseaudio-doc..." and ">>> clementine: disable-backtrace.patch" (applying patches). The only way to fix it is to do sudo chmod 1777 /tmp, but that requires sudo permissions, so it can't be easily done in CI. Turns out this was a libgpod issue; see #13010 (closed).

As for known bugs:

• setting the analyzer to Sonogram causes the program to close with a SIGINT; to fix this, the user has to remove the analyzer settings from ~/.config/Clementine/Clementine.conf. This appears to be caused somewhere in libQt5Gui, but I can't debug it much further due to the lack of debug symbols (might try getting debug symbols working myself if needed - currently just opened an issue for it: #13041 (closed)). Also doesn't really explain where in Clementine's code this happens.
• visualization presets aren't found, and in the config the preset path is set to "&Invalid()"; seems to be behaving quite laggily anyways; changing the quality setting results in

  Thread 1 "clementine" received signal SIGSEGV, Segmentation fault.
  0x00007ffff711e378 in ShaderEngine::loadPresetShaders(Pipeline&, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&) () from /usr/lib/libprojectM.so.3

Considering that Clementine hasn't seen a proper upstream release since 2016, and I'm assuming this will continue further into the future, my plan for updating the package is to update it to the latest beta release at least every month, or more often in case of important patches.