fix: add type ignore for requests import and sync baseline

Add type: ignore[import-untyped] comment for the local requests
import in _setup_sse_connection to suppress mypy warning about
missing stubs.

Update mypy-baseline.txt to reflect the 3 fixed violations.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

Author: gustavohstrassburger

mypy-baseline.txt

@@ -23,13 +23,10 @@ posthog/client.py:0: note: Hint: "python3 -m pip install types-six"
 posthog/client.py:0: error: Name "queue" already defined (by an import)  [no-redef]
 posthog/client.py:0: error: Need type annotation for "queue"  [var-annotated]
 posthog/client.py:0: error: Incompatible types in assignment (expression has type "Any | list[Any]", variable has type "None")  [assignment]
-posthog/client.py:0: error: Incompatible types in assignment (expression has type "dict[Any, Any]", variable has type "None")  [assignment]
 posthog/client.py:0: error: "None" has no attribute "__iter__" (not iterable)  [attr-defined]
 posthog/client.py:0: error: Statement is unreachable  [unreachable]
 posthog/client.py:0: error: Right operand of "and" is never evaluated  [unreachable]
 posthog/client.py:0: error: Incompatible types in assignment (expression has type "Poller", variable has type "None")  [assignment]
 posthog/client.py:0: error: "None" has no attribute "start"  [attr-defined]
-posthog/client.py:0: error: Statement is unreachable  [unreachable]
-posthog/client.py:0: error: Statement is unreachable  [unreachable]
 posthog/client.py:0: error: Name "urlparse" already defined (possibly by an import)  [no-redef]
 posthog/client.py:0: error: Name "parse_qs" already defined (possibly by an import)  [no-redef]

posthog/client.py

@@ -2267,7 +2267,7 @@ def _setup_sse_connection(self):
 
         try:
             # Use requests with stream=True for SSE
-            import requests
+            import requests  # type: ignore[import-untyped]
 
             url = f"{self.host}/flags/definitions/stream?api_key={self.api_key}"
             headers = {