test: Use 4 spaces for indentation

Author: MarcoFalke

test/functional/wallet_importdescriptors.py

@@ -55,7 +55,7 @@ def test_importdesc(self, req, success, error_code=None, error_message=None, war
         result = wrpc.importdescriptors([req])
         observed_warnings = []
         if 'warnings' in result[0]:
-           observed_warnings = result[0]['warnings']
+            observed_warnings = result[0]['warnings']
         assert_equal("\n".join(sorted(warnings)), "\n".join(sorted(observed_warnings)))
         assert_equal(result[0]['success'], success)
         if error_code is not None: