BUG/MEDIUM: threads/cli: fix "show sess" locking on release

The recent thread updates on the CLI broke "show sess" by unlocking
the stream twice instead of lock+unlock. No backport is needed.
diff --git a/src/stream.c b/src/stream.c
index 8f81622..48c4ba5 100644
--- a/src/stream.c
+++ b/src/stream.c
@@ -3252,7 +3252,7 @@
 static void cli_release_show_sess(struct appctx *appctx)
 {
 	if (appctx->st2 == STAT_ST_LIST) {
-		HA_SPIN_UNLOCK(STRMS_LOCK, &streams_lock);
+		HA_SPIN_LOCK(STRMS_LOCK, &streams_lock);
 		if (!LIST_ISEMPTY(&appctx->ctx.sess.bref.users))
 			LIST_DEL(&appctx->ctx.sess.bref.users);
 		HA_SPIN_UNLOCK(STRMS_LOCK, &streams_lock);