Improve few errdetail messages introduced in commit 0d48d393d4.

Based on suggestions by Tom Lane

Reported-by: Kyotaro Horiguchi <horikyota.ntt@gmail.com>
Author: Zhijie Hou <houzj.fnst@fujitsu.com>
Reviewed-by: Amit Kapila <amit.kapila16@gmail.com>
Discussion: https://postgr.es/m/20250916.114644.275726106301941878.horikyota.ntt@gmail.com

src/backend/replication/logical/worker.c

@@ -4790,8 +4790,7 @@ stop_conflict_info_retention(RetainDeadTuplesData *rdt_data)
 		ereport(LOG,
 				errmsg("logical replication worker for subscription \"%s\" has stopped retaining the information for detecting conflicts",
 					   MySubscription->name),
-				errdetail("Retention is stopped as the apply process is not advancing its xmin within the configured max_retention_duration of %u ms.",
+				errdetail("Retention is stopped because the apply process has not caught up with the publisher within the configured max_retention_duration."));
-						  MySubscription->maxretention));
 	}
 
 	Assert(!TransactionIdIsValid(MyLogicalRepWorker->oldest_nonremovable_xid));
@@ -4819,9 +4818,8 @@ resume_conflict_info_retention(RetainDeadTuplesData *rdt_data)
 			errmsg("logical replication worker for subscription \"%s\" will resume retaining the information for detecting conflicts",
 				   MySubscription->name),
 			MySubscription->maxretention
-			? errdetail("Retention is re-enabled as the apply process is advancing its xmin within the configured max_retention_duration of %u ms.",
+			? errdetail("Retention is re-enabled because the apply process has caught up with the publisher within the configured max_retention_duration.")
-						MySubscription->maxretention)
+			: errdetail("Retention is re-enabled because max_retention_duration has been set to unlimited."));
-			: errdetail("Retention is re-enabled as max_retention_duration is set to unlimited."));
 
 	/*
 	 * Restart the worker to let the launcher initialize

src/test/subscription/t/035_conflicts.pl

@@ -633,7 +633,7 @@ $node_B->reload;
 # Confirm that the retention resumes
 $node_A->wait_for_log(
 	qr/logical replication worker for subscription "tap_sub_a_b" will resume retaining the information for detecting conflicts
-.*DETAIL:.* Retention is re-enabled as max_retention_duration is set to unlimited.*/,
+.*DETAIL:.* Retention is re-enabled because max_retention_duration has been set to unlimited.*/,
 	$log_offset);
 
 ok( $node_A->poll_query_until(