fix: postgres migration script
-- Migration generated by the command below; DO NOT EDIT.
-- hydra:generate hydra migrate gen
-ALTER TABLE hydra_oauth2_trusted_jwt_bearer_issuer DROP CONSTRAINT hydra_oauth2_trusted_jwt_bearer_issuer_key_set_fkey;
+ALTER TABLE hydra_oauth2_trusted_jwt_bearer_issuer DROP CONSTRAINT IF EXISTS hydra_oauth2_trusted_jwt_bearer_issuer_key_set_fkey;
+ALTER TABLE hydra_oauth2_trusted_jwt_bearer_issuer DROP CONSTRAINT IF EXISTS hydra_oauth2_trusted_jwt_bearer_issuer_key_set_key_id_fkey;
