build: use gradle from docker image

Prevents downloading gradle every build

Change-Id: I920d51bb7712e2f6aaf3f6845bae3f98bcb02ff6
diff --git a/compile.sh b/compile.sh
index 639ffc2..497f11a 100755
--- a/compile.sh
+++ b/compile.sh
@@ -52,9 +52,9 @@
     fi
     if [[ $DAEMON_ONLY -eq 0 ]]; then
         if [[ $RELEASE -eq 1 ]]; then
-            cd $TOP && ./gradlew $GRADLE_PROPERTIES assembleRelease
+            cd $TOP && gradle $GRADLE_PROPERTIES assembleRelease
         else
-            cd $TOP && ./gradlew $GRADLE_PROPERTIES assembleDebug
+            cd $TOP && gradle $GRADLE_PROPERTIES assembleDebug
         fi
     fi
 else