[CTS] Treat skipped tests as passes

The conformance tests skip tests when a devices returns
`UR_RESULT_ERROR_UNSUPPORTED_FEATURE` and the feature under test is
optional. As such, skipped tests count as passes because the device has
exhibiting valid behaviour. This patch changes how CTS pass rates are
calculated to match.

Author: kbenzie

scripts/ctest_parser.py

@@ -33,8 +33,8 @@ def summarize_results(results):
     total_failed = len(results['Failed'])
     total_crashed = total - (total_passed + total_skipped + total_failed)
 
-    pass_rate_incl_skipped = percent(total_passed, total)
-    pass_rate_excl_skipped = percent(total_passed, total - total_skipped)
+    pass_rate_incl_skipped = percent(total_passed + total_skipped, total)
+    pass_rate_excl_skipped = percent(total_passed, total)
 
     skipped_rate = percent(total_skipped, total)
     failed_rate = percent(total_failed, total)