[Mem0] Update dependencies and make the package lighter (#1708)

Co-authored-by: Dev-Khant <devkhant24@gmail.com>

pyproject.toml

@@ -1,6 +1,6 @@
 [tool.poetry]
 name = "mem0ai"
-version = "0.0.19"
+version = "0.0.20"
 description = "Long-term memory for AI Agents"
 authors = ["Mem0 <founders@mem0.ai>"]
 exclude = [
@@ -22,7 +22,6 @@ openai = "^1.33.0"
 posthog = "^3.5.0"
 pytz = "^2024.1"
 sqlalchemy = "^2.0.31"
-litellm = "^1.42.7"
 
 [tool.poetry.group.test.dependencies]
 pytest = "^8.2.2"