Add litellm extra (#1413)

Author: alexmojaki

pyproject.toml

@@ -79,6 +79,7 @@ mysql = ["opentelemetry-instrumentation-mysql >= 0.42b0"]
 sqlite3 = ["opentelemetry-instrumentation-sqlite3 >= 0.42b0"]
 aws-lambda = ["opentelemetry-instrumentation-aws-lambda >= 0.42b0"]
 google-genai = ["opentelemetry-instrumentation-google-genai >= 0"]
+litellm = ["openinference-instrumentation-litellm >= 0"]
 
 [project.urls]
 Homepage = "https://logfire.pydantic.dev/"