component AP gateway: fix method retrieval in ap_request:

following recent refactoring to use snake_case, the former method retrieve was broken,
this patch fixes it.

libervia/backend/plugins/plugin_comp_ap_gateway/http_server.py

@@ -1029,7 +1029,7 @@ class HTTPAPGServer(web_resource.Resource):
                     request.method.decode().upper(), []
             ):
                 raise exceptions.DataError(f"Invalid request type: {request_type!r}")
-            method = getattr(self, f"AP{request_type.title()}Request")
+            method = getattr(self, f"ap_{request_type}_request")
             ret_data = await method(
                 request, data, account_jid, node, ap_account, ap_url, signing_actor
             )