ziafazal/api-fix-bug-progress-tab: Made no of completions as percentage

@dsego @mattdrayer This should fix the issue MCKIN-1944. Now api is sending completions as percentage instead of total completions by user. Also sending proficiency points as integers to make it consistent with apros .
user_completions are calculated are a result of `count` on queryset which would return either 0 or a an integer greater than 0