fix unit test to disable application signals dimensions

Author: liustve

aws-opentelemetry-distro/tests/amazon/opentelemetry/distro/exporter/aws/metrics/test_aws_cloudwatch_emf_exporter.py

@@ -2,6 +2,7 @@
 # SPDX-License-Identifier: Apache-2.0
 
 import json
+import os
 import time
 import unittest
 from unittest.mock import Mock, patch
@@ -358,8 +359,10 @@ def test_create_emf_log(self):
         # Check that the result is JSON serializable
         json.dumps(result)  # Should not raise exception
 
+    @patch.dict("os.environ", {"OTEL_METRICS_ADD_APPLICATION_SIGNALS_DIMENSIONS": "false"})
     def test_create_emf_log_with_resource(self):
         """Test EMF log creation with resource attributes."""
+
         # Create test records
         gauge_record = self.exporter._create_metric_record("gauge_metric", "Count", "Gauge")
         gauge_record.value = 50.0
@@ -395,8 +398,10 @@ def test_create_emf_log_with_resource(self):
         self.assertEqual(set(cw_metrics["Dimensions"][0]), {"env", "service"})
         self.assertEqual(cw_metrics["Metrics"][0]["Name"], "gauge_metric")
 
+    @patch.dict("os.environ", {"OTEL_METRICS_ADD_APPLICATION_SIGNALS_DIMENSIONS": "false"})
     def test_create_emf_log_without_dimensions(self):
         """Test EMF log creation with metrics but no dimensions."""
+
         # Create test record without attributes (no dimensions)
         gauge_record = self.exporter._create_metric_record("gauge_metric", "Count", "Gauge")
         gauge_record.value = 75.0