add doc comment for type hinting

Author: Ben Osborne

src/Traits/QueryCacheable.php

@@ -5,6 +5,11 @@
 use Rennokki\QueryCache\FlushQueryCacheObserver;
 use Rennokki\QueryCache\Query\Builder;
 
+/**
+ * @method static \Illuminate\Database\Query\Builder|static cacheForever()
+ * @method static \Illuminate\Database\Query\Builder|static dontCache()
+ * @method static \Illuminate\Database\Query\Builder|static doNotCache()
+ */
 trait QueryCacheable
 {
     /**