keyIsExpired checks server.loading before calling getExpire (#11393)

Seems excessive to call getExpire if we don't need it.
This can maybe have some speedup on AOF file loading (saving a dictFind call)

Co-authored-by: lvshuning <lvshuning@meituan.com>

src/db.c

@@ -1612,14 +1612,14 @@ void propagateDeletion(redisDb *db, robj *key, int lazy) {
 
 /* Check if the key is expired. */
 int keyIsExpired(redisDb *db, robj *key) {
+    /* Don't expire anything while loading. It will be done later. */
+    if (server.loading) return 0;
+
     mstime_t when = getExpire(db,key);
     mstime_t now;
 
     if (when < 0) return 0; /* No expire for this key */
 
-    /* Don't expire anything while loading. It will be done later. */
-    if (server.loading) return 0;
-
     now = commandTimeSnapshot();
 
     /* The key expired if the current (virtual or real) time is greater