Add fixture to load API keys from environment variables

tests/test_chat_models.py

@@ -17,6 +17,7 @@
 }
 
 
+@pytest.mark.usefixtures('api_keys')
 @pytest.mark.parametrize(
     'llm, expected',
     [(k, v) for _, (k, v) in enumerate(name2cls.items())]
@@ -30,6 +31,7 @@ def test_create_chat_model_wo_seed(
     assert isinstance(create_chat_model(llm), expected)
 
 
+@pytest.mark.usefixtures('api_keys')
 @pytest.mark.parametrize(
     'llm, seed, expected',
     [(k, i, v) for i, (k, v) in enumerate(name2cls.items())]
@@ -52,6 +54,7 @@ def test_create_chat_model_w_invalid_llm() -> None:
         create_chat_model('invalid')
 
 
+@pytest.mark.usefixtures('api_keys')
 @pytest.mark.integration
 @pytest.mark.skipif(
     os.getenv("OPENAI_API_KEY") is None,
@@ -71,6 +74,7 @@ def test_create_chat_model_for_ChatOpenAI_integration(llm: str) -> None:
     assert isinstance(create_chat_model(llm), ChatOpenAI)
 
 
+@pytest.mark.usefixtures('api_keys')
 @pytest.mark.integration
 @pytest.mark.skipif(
     os.getenv("GROQ_API_KEY") is None,
@@ -96,6 +100,7 @@ def test_create_chat_model_for_ChatGroq_integration(llm: str) -> None:
     assert isinstance(create_chat_model(llm), ChatGroq)
 
 
+@pytest.mark.usefixtures('api_keys')
 @pytest.mark.integration
 @pytest.mark.skipif(
     os.getenv("GOOGLE_API_KEY") is None,