Update sbt command

Author: liufengyun

Diff for: .github/workflows/ci.yaml

@@ -22,7 +22,7 @@ jobs:
         uses: liufengyun/actions@v2
         with:
           container: lampepfl/dotty-windows:2020-10-02
-          command: sbt ";compile ;test"
+          command: sbt test
 
   test_bootstrapped-windows:
     runs-on: [self-hosted, Windows]
@@ -35,7 +35,7 @@ jobs:
         uses: liufengyun/actions@v2
         with:
           container: lampepfl/dotty-windows:2020-10-02
-          command: sbt ";dotty-bootstrapped/compile ;dotty-bootstrapped/test"
+          command: sbt dotty-bootstrapped/test
 
       # - name: Scala.js Test
       #   uses: liufengyun/actions@v1