fix: add missing http_trigger_version_seq grants

Author: HugoCasa

backend/migrations/20250526173025_http_trigger_seq_grants.down.sql

@@ -0,0 +1 @@
+-- Add down migration script here

backend/migrations/20250526173025_http_trigger_seq_grants.up.sql

@@ -0,0 +1,3 @@
+-- Add up migration script here
+GRANT ALL ON SEQUENCE http_trigger_version_seq TO windmill_user;
+GRANT ALL ON SEQUENCE http_trigger_version_seq TO windmill_admin;