fix: litellm test errors

Author: constantinius

sentry_sdk/integrations/litellm.py

@@ -84,7 +84,7 @@ def _map_item(item: "Dict[str, Any]") -> "Dict[str, Any]":
         if item.get("type") == "image_url":
             image_url = item.get("image_url") or {}
             url = image_url.get("url", "")
-            if url.startswith("data:"):
+            if url.startswith("data:") and ";base64," in url:
                 try:
                     mime_type, content = parse_data_uri(url)
                     return {