Hotfix/global agent manager workaround (#3157)

* Add indirection layer to entry point

* Get around singleton pattern for AgentManager to fix tests

autogpt/main.py

@@ -1,5 +1,4 @@
 """The application entry point.  Can be invoked by a CLI or any other front end application."""
-
 import logging
 import sys
 from pathlib import Path

tests/test_agent_manager.py

@@ -8,6 +8,9 @@ from tests.utils import requires_api_key
 
 @pytest.fixture
 def agent_manager():
+    # Hack, real gross. Singletons are not good times.
+    if AgentManager in AgentManager._instances:
+        del AgentManager._instances[AgentManager]
     return AgentManager()
 
 
@@ -23,7 +26,7 @@ def prompt():
 
 @pytest.fixture
 def model():
-    return "gpt-4"
+    return "gpt-3.5-turbo"
 
 
 @requires_api_key("OPENAI_API_KEY")