ci: trying multi-line and shell for build.sh

Author: suztomo

.github/workflows/ci.yaml

@@ -39,8 +39,14 @@ jobs:
         cd play-services
         curl --output play-services-basement-8.3.0.aar https://dl.google.com/dl/android/maven2/com/google/android/gms/play-services-basement/8.3.0/play-services-basement-8.3.0.aar
         unzip play-services-basement-8.3.0.aar
-        mvn install:install-file -Dfile=classes.jar -DgroupId=com.google.android.google-play-services -DartifactId=google-play-services -Dversion=1 -Dpackaging=jar
-    - run: .kokoro/build.bat
+        mvn install:install-file \
+            -Dfile=classes.jar \
+            -DgroupId=com.google.android.google-play-services \
+            -DartifactId=google-play-services \
+            -Dversion=1 \
+            -Dpackaging=jar
+    - run: .kokoro/build.sh
+      shell: bash
       env:
         JOB_TYPE: test
   dependencies: