[do not merge] add dummy community_build job to satisfy required

Author: griggt

.github/workflows/ci.yaml

@@ -133,6 +133,14 @@ jobs:
         run: sbt ";sjsJUnitTests/test ;sjsCompilerTests/test"
         shell: cmd
 
+  community_build:
+    runs-on: [self-hosted, Linux]
+    container: lampepfl/dotty:2020-04-24
+
+    steps:
+      - name: Test
+        run: /bin/true
+
   community_build_a:
     runs-on: [self-hosted, Linux]
     container: lampepfl/dotty:2020-04-24