Fix multi-line comment to use block format, not consecutive -- lines

Same CODE_STYLE.md fix as reconcile-object-functions' commit for
sql/object_reference.sql, applied to this update script's identical
client_min_messages explanation.

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

Author: jnasbyupgrade

sql/object_reference--0.1.0--stable.sql

@@ -51,9 +51,11 @@
  * comparison of every recreated function/view against a fresh install of the
  * current version backs this file -- see the containing PR's description).
  */
--- SET LOCAL, not SET: this script runs inside ALTER EXTENSION UPDATE's
--- implicit transaction, so LOCAL reverts automatically once it commits --
--- see sql/object_reference.sql's own identical comment on this same point.
+/*
+ * SET LOCAL, not SET: this script runs inside ALTER EXTENSION UPDATE's
+ * implicit transaction, so LOCAL reverts automatically once it commits --
+ * see sql/object_reference.sql's own identical comment on this same point.
+ */
 SET LOCAL client_min_messages = WARNING;
 
 CREATE SCHEMA __object_reference;