cov: Add comment on SCHEMA in test fixtures

test/fixtures/schema.sql

@@ -21,6 +21,9 @@ CREATE SCHEMA extensions;
 CREATE SCHEMA v1;
 CREATE SCHEMA v2;
 
+COMMENT ON SCHEMA v1 IS 'v1 schema';
+COMMENT ON SCHEMA v2 IS 'v2 schema';
+
 --
 -- Name: plpgsql; Type: EXTENSION; Schema: -; Owner: -
 --