chore: Update gemini_model_example.py (#3436)

Author: fengju0213

examples/models/gemini_model_example.py

@@ -11,7 +11,7 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 # ========= Copyright 2023-2024 @ CAMEL-AI.org. All Rights Reserved. =========
-from agentops.client import os
+import os
 
 from camel.agents import ChatAgent
 from camel.configs import GeminiConfig