8317846: Typo in API documentation of classes IdentityHashMap

Reviewed-by: mli, jpai

src/java.base/share/classes/java/util/IdentityHashMap.java

@@ -267,7 +267,7 @@ private void init(int initCapacity) {
     }
 
     /**
-     * Constructs a new identity hash map containing the keys-value mappings
+     * Constructs a new identity hash map containing the key-value mappings
      * in the specified map.
      *
      * @param m the map whose mappings are to be placed into this map