Squish: override startApplication in startCreatorTryingClang()

Change-Id: I6cb16c2a93ca46503f056c558eb8a6a2b33153d7
Reviewed-by: Christian Stenger <christian.stenger@theqtcompany.com>

tests/system/shared/clang.py

@@ -42,6 +42,7 @@ def startCreatorTryingClang():
     except:
         # ClangCodeModel plugin has not been built - start without it
         test.warning("ClangCodeModel plugin not available - performing test without.")
+        overrideStartApplication()
         startApplication("qtcreator" + SettingsPath)
         return False