test bootstrapped/test

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Disable other tests to see if we can get `bootstrapped/test` green.

Author: liufengyun

.appveyor.yml

@@ -14,7 +14,7 @@ init:
 build_script:
   - cmd: sbt dotty-bootstrapped/compile
 test_script:
-  - cmd: sbt "dotty-bootstrapped/dotc tests\pos\HelloWorld.scala"
-  - cmd: sbt test
+  # - cmd: sbt "dotty-bootstrapped/dotc tests\pos\HelloWorld.scala"
+  # - cmd: sbt test
   - cmd: sbt dotty-bootstrapped/test
-  - cmd: sbt sjsJUnitTests/test
+  # - cmd: sbt sjsJUnitTests/test