Add test for curl debug mixin without OAuth

Added test case for the fallback path in CurlDebugMixin when OAuth token is not available,
ensuring 100% test coverage for the mixin class.

Author: jpstroop

tests/utils/test_curl_debug_mixin.py

@@ -116,3 +116,19 @@ def test_debug_mode_integration(capsys):
     assert "test/endpoint" in captured.out
     assert "param1=value1" in captured.out
     assert "test_token" in captured.out
+
+
+def test_build_curl_command_without_oauth():
+    """Test curl command generation when oauth is not available"""
+    # Create a bare mixin instance without oauth
+    mixin = CurlDebugMixin()
+
+    # Generate a curl command
+    result = mixin._build_curl_command(
+        url="https://api.fitbit.com/1/user/-/test.json", http_method="GET"
+    )
+
+    # Verify that the fallback auth header is used
+    assert '-H "Authorization: Bearer TOKEN"' in result
+    assert "curl -v" in result
+    assert "'https://api.fitbit.com/1/user/-/test.json'" in result