Fix pydantic version constraint for composio compat

backend/requirements.txt

@@ -1,14 +1,14 @@
 fastapi==0.109.2
 uvicorn[standard]==0.27.1
 sqlalchemy==2.0.25
-pydantic==2.6.1
+pydantic>=2.6.4
 pydantic-settings==2.1.0
 python-jose[cryptography]==3.3.0
 passlib[bcrypt]==1.7.4
 bcrypt==4.0.1
 python-multipart==0.0.6
-httpx==0.26.0
-cryptography==42.0.2
+httpx>=0.26.0
+cryptography>=42.0.2
 jsonschema==4.21.1
 python-dotenv==1.0.1
 psutil==5.9.8