Remove duplicated comment in get_relation_constraints

The check for non-inheritable constraints is performed later, and the
same comment is included at that point.

While we're here, remove one extraneous blank line.

Author: jian he <jian.universality@gmail.com>
Reviewed-by: Kirill Reshke <reshkekirill@gmail.com>
Reviewed-by: Richard Guo <guofenglinux@gmail.com>
Discussion: https://postgr.es/m/CACJufxETi6x86S8EkH8mRfOcm2AenoE9t1pyCFVMpU34gVhF3w@mail.gmail.com

src/backend/optimizer/util/plancat.c

@@ -1303,8 +1303,7 @@ get_relation_constraints(PlannerInfo *root,
 
 			/*
 			 * If this constraint hasn't been fully validated yet, we must
-			 * ignore it here.  Also ignore if NO INHERIT and we weren't told
-			 * that that's safe.
+			 * ignore it here.
 			 */
 			if (!constr->check[i].ccvalid)
 				continue;
@@ -1321,7 +1320,6 @@ get_relation_constraints(PlannerInfo *root,
 			if (constr->check[i].ccnoinherit && !include_noinherit)
 				continue;
 
-
 			cexpr = stringToNode(constr->check[i].ccbin);
 
 			/*