fix: type warning on new_context (#558)

* fix type warning on `new_context`

* changeset

---------

Co-authored-by: Manoel Aranda Neto <marandaneto@gmail.com>

Author: itsaphel

.sampo/changesets/forthright-guardian-sampsa.md

@@ -0,0 +1,5 @@
+---
+pypi/posthog: patch
+---
+
+fix: type warning on new_context

posthog/__init__.py

@@ -73,7 +73,11 @@
 """Context management."""
 
 
-def new_context(fresh=False, capture_exceptions=True, client=None):
+def new_context(
+    fresh: bool = False,
+    capture_exceptions: bool = True,
+    client: Optional[Client] = None,
+):
     """
     Create a new context scope that will be active for the duration of the with block.