Ignore Unity dlls when running tests

Author: shana

appveyor.yml

@@ -53,6 +53,9 @@ build:
   project: GitHub.Unity.sln
   verbosity: minimal
 test:
+  assemblies:
+    except:
+      - '**\*.TestRunner.dll'
   categories:
     except:
     - DoNotRunOnAppVeyor