fix: Remove unused type:ignore on async method overrides

With AsyncHttpTransport always defined as a real class, mypy properly
sees the class hierarchy and no longer flags _send_envelope and
_send_request as incompatible overrides.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: BYK

sentry_sdk/transport.py

@@ -856,7 +856,7 @@ def _get_header_value(
     ) -> "Optional[str]":
         return _get_httpcore_header_value(response, header)
 
-    async def _send_envelope(self: "Self", envelope: "Envelope") -> None:  # type: ignore[override]
+    async def _send_envelope(self: "Self", envelope: "Envelope") -> None:
         _prepared_envelope = self._prepare_envelope(envelope)
         if _prepared_envelope is not None:
             envelope, body, headers = _prepared_envelope
@@ -868,7 +868,7 @@ async def _send_envelope(self: "Self", envelope: "Envelope") -> None:  # type: i
             )
         return None
 
-    async def _send_request(  # type: ignore[override]
+    async def _send_request(
         self: "Self",
         body: bytes,
         headers: "Dict[str, str]",