Mock telemetry in pytest tests (#3340)

* Add telemetry mocking for pytest tests

- Mock telemetry by default for all tests except telemetry-specific tests
- Add @pytest.mark.telemetry marker for real telemetry tests
- Reduce test overhead and improve isolation

* Fix telemetry test isolation

- Properly isolate telemetry tests from mocking environment
- Preserve API keys and other necessary environment variables
- Ensure telemetry tests can run with real telemetry instances

tests/telemetry/test_telemetry.py

@@ -1,4 +1,5 @@
 import os
+import threading
 from unittest.mock import patch
 
 import pytest
@@ -11,12 +12,16 @@ from opentelemetry import trace
 
 @pytest.fixture(autouse=True)
 def cleanup_telemetry():
-    """Automatically clean up Telemetry singleton between tests."""
     Telemetry._instance = None
+    if hasattr(Telemetry, "_lock"):
+        Telemetry._lock = threading.Lock()
     yield
     Telemetry._instance = None
+    if hasattr(Telemetry, "_lock"):
+        Telemetry._lock = threading.Lock()
 
 
+@pytest.mark.telemetry
 @pytest.mark.parametrize(
     "env_var,value,expected_ready",
     [
@@ -36,6 +41,7 @@ def test_telemetry_environment_variables(env_var, value, expected_ready):
             assert telemetry.ready is expected_ready
 
 
+@pytest.mark.telemetry
 def test_telemetry_enabled_by_default():
     """Test that telemetry is enabled by default."""
     with patch.dict(os.environ, {}, clear=True):
@@ -44,6 +50,7 @@ def test_telemetry_enabled_by_default():
             assert telemetry.ready is True
 
 
+@pytest.mark.telemetry
 @patch("crewai.telemetry.telemetry.logger.error")
 @patch(
     "opentelemetry.exporter.otlp.proto.http.trace_exporter.OTLPSpanExporter.export",
@@ -76,6 +83,7 @@ def test_telemetry_fails_due_connect_timeout(export_mock, logger_mock):
     logger_mock.assert_called_once_with(error)
 
 
+@pytest.mark.telemetry
 def test_telemetry_singleton_pattern():
     """Test that Telemetry uses the singleton pattern correctly."""
     Telemetry._instance = None