fix UR_DDI python class init

[pbalcer]

This patch fixes all issues that were preventing the python bindings from initializing the loader.

[pbalcer]

The loader PR has a conflict with the recent change to the pull_request.yml workflow (which I'm removing in favor of one that uses cmake targets) that added a check to verify if the python module even imports (#89). That inspired me to add simple test infrastructure using ctest and create a python that actually tried to run the python bindings. This was so that I could add running ctest to the cmake workflow.

Predictably, the python module didn't work ;) Hence this patch.

Once this is merged, I'll either update the loader PR to include the test or create a new PR.

[FranklandJack]

LGTM.

[kbenzie]

LGTM