Fix CI failure introduced in commit 851f6649cc.

The test added in commit 851f6649cc uses a backup taken from a node
created by the previous test to perform standby related checks. On
Windows, however, the standby failed to start with the following error:
FATAL:  could not rename file "backup_label" to "backup_label.old": Permission denied

This occurred because some background sessions from the earlier test were
still active. These leftover processes continued accessing the parent
directory of the backup_label file, likely preventing the rename and
causing the failure. Ensuring that these sessions are cleanly terminated
resolves the issue in local testing.

Additionally, the has_restoring => 1 option has been removed, as it was
not required by the new test.

Reported-by: Robert Haas <robertmhaas@gmail.com>
Backpatch-through: 17
Discussion: https://postgr.es/m/CA+TgmobdVhO0ckZfsBZ0wqDO4qHVCwZZx8sf=EinafvUam-dsQ@mail.gmail.com

src/test/recovery/t/046_checkpoint_logical_slot.pl

@@ -138,6 +138,13 @@ eval {
 };
 is($@, '', "Logical slot still valid");
 
+# If we send \q with $<psql_session>->quit the command can be sent to the
+# session already closed. So \q is in initial script, here we only finish
+# IPC::Run
+$xacts->{run}->finish;
+$checkpoint->{run}->finish;
+$logical->{run}->finish;
+
 # Verify that the synchronized slots won't be invalidated immediately after
 # synchronization in the presence of a concurrent checkpoint.
 my $primary = $node;
@@ -153,8 +160,7 @@ $primary->backup($backup_name);
 my $standby = PostgreSQL::Test::Cluster->new('standby');
 $standby->init_from_backup(
 	$primary, $backup_name,
-	has_streaming => 1,
-	has_restoring => 1);
+	has_streaming => 1);
 
 my $connstr_1 = $primary->connstr;
 $standby->append_conf(