compile_and_test_for_board: add logger info for 'has_test'

Add a logger info printing if the application has a test.

dist/tools/compile_and_test_for_board/compile_and_test_for_board.py

@@ -220,9 +220,11 @@ class RIOTApplication():
         try:
             self.make(self.TEST_AVAILABLE_TARGETS)
         except subprocess.CalledProcessError:
-            return False
+            has_test = False
         else:
-            return True
+            has_test = True
+        self.logger.info('Application has test: %s', has_test)
+        return has_test
 
     def board_is_supported(self):
         """Return if current board is supported."""