fix(android): use gradle instead of ./gradlew in test suite

The Android example doesn't have a gradle wrapper, so use the system gradle command.

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

Author: abueide

examples/android/tests/test-suite.yaml

@@ -12,7 +12,7 @@ is_strict: true
 processes:
   # Phase 1: Build - runs first (no dependency)
   build-app:
-    command: "./gradlew assembleDebug"
+    command: "gradle assembleDebug"
     availability:
       restart: "no"