AK+LibGUI: Pass predicate to *_matching() methods by const reference

Author: https://github.com/obyknovenius
Commit: a0a4d169f4
Pull-request: https://github.com/SerenityOS/serenity/pull/13641
Reviewed-by: https://github.com/ldm5180 ✅

AK/HashTable.h

@@ -422,7 +422,7 @@ public:
     }
 
     template<typename TUnaryPredicate>
-    bool remove_all_matching(TUnaryPredicate predicate)
+    bool remove_all_matching(TUnaryPredicate const& predicate)
     {
         size_t removed_count = 0;
         for (size_t i = 0; i < m_capacity; ++i) {