Only run bootstrapped compilation tests on windows

Author: liufengyun

.appveyor.yml

@@ -17,7 +17,8 @@ test_script:
   - pwd
   # - bash project/scripts/sbt test
   # - bash project/scripts/cmdTests
-  - bash project/scripts/sbt "dotty-bootstrapped/test"
+  # - bash project/scripts/sbt "dotty-bootstrapped/test"
+  - bash project/scripts/sbt "dotty-bootstrapped/testCompilation"
   - bash project/scripts/bootstrapCmdTests
 cache:
   - C:\sbt\