fix test

Author: danielhochman

exporter/opentelemetry-exporter-otlp-proto-common/tests/test_attribute_encoder.py

@@ -88,7 +88,7 @@ def test_encode_attributes_error_logs_key(self):
             result = _encode_attributes({"a": 1, "bad_key": None, "b": 2})
 
         self.assertEqual(len(error.records), 1)
-        self.assertEqual(error.records[0].msg, f"Failed to encode key %s: %s")
+        self.assertEqual(error.records[0].msg, "Failed to encode key %s: %s")
         self.assertEqual(error.records[0].args[0], "bad_key")
         self.assertIsInstance(error.records[0].args[1], Exception)
         self.assertEqual(