Update requirements.txt to latest package versions

Updated package versions in requirements.txt to latest.

requirements.txt

@@ -1,7 +1,7 @@
-fastapi==0.104.1
-uvicorn==0.24.0
-google-generativeai==0.3.0
-python-dotenv==1.0.0
-pydantic==2.5.0
-aiofiles==23.2.1
-python-multipart==0.0.6
+fastapi
+uvicorn
+google-genai
+python-dotenv
+pydantic
+aiofiles
+python-multipart