ci: add debug artifacts for test_idf_tools

.gitlab/ci/host-test.yml

@@ -180,6 +180,11 @@ test_idf_py:
 
 test_idf_tools:
   extends: .host_test_template
+  artifacts:
+    when: on_failure
+    paths:
+      - tools/tools.new.json
+    expire_in: 1 week
   script:
     # Remove Xtensa and ULP toolchains from the PATH, tests will expect a clean environment
     - export PATH=$(p=$(echo $PATH | tr ":" "\n" | grep -v "/root/.espressif/tools\|/opt/espressif" | tr "\n" ":"); echo ${p%:})

tools/test_idf_tools/test_idf_tools.py

@@ -124,7 +124,7 @@ class TestMaintainer(unittest.TestCase):
             json_old = f.read()
         with open(os.path.join(idf_path, 'tools/tools.new.json'), 'r') as f:
             json_new = f.read()
-        self.assertEqual(json_old, json_new)
+        self.assertEqual(json_old, json_new, "Please check 'tools/tools.new.json' to find a cause!")
 
 
 if __name__ == '__main__':