fix(ci): rename pylint-disallowed test field, add changelog fragment

pylint's disallowed-name check rejected the field name "bar" in
test_configuration_can_be_overridden. Also adds the missing
.changelog/4766.added fragment required by the changelog check.

Author: ocelotl

.changelog/4766.added

@@ -0,0 +1 @@
+`opentelemetry-instrumentation`: add `configuration` opt-in attribute on `BaseInstrumentor` for declarative-config validation, and set it on `URLLib3Instrumentor` via `URLLib3InstrumentorConfig`

opentelemetry-instrumentation/tests/test_instrumentor.py

@@ -52,13 +52,13 @@ def test_configuration_defaults_to_none(self):
 
     def test_configuration_can_be_overridden(self):
         @dataclass
-        class FooConfig:
-            bar: str | None = None
+        class SampleConfig:
+            excluded_urls: str | None = None
 
         class ConfiguredInstrumentor(self.Instrumentor):
-            configuration = FooConfig
+            configuration = SampleConfig
 
-        self.assertIs(ConfiguredInstrumentor.configuration, FooConfig)
+        self.assertIs(ConfiguredInstrumentor.configuration, SampleConfig)
         self.assertIsNone(self.Instrumentor.configuration)
 
     @patch("opentelemetry.instrumentation.instrumentor._LOG")