minor fixes

Author: iliakan

1-js/05-data-types/08-weakmap-weakset/article.md

@@ -284,7 +284,7 @@ The most notable limitation of `WeakMap` and `WeakSet` is the absence of iterati
 
 `WeakSet` is `Set`-like collection that stores only objects and removes them once they become inaccessible by other means.
 
-Their main advantages are that they have weak reference to objects, so they can easily be removed by garbage colector.
+Their main advantages are that they have weak reference to objects, so they can easily be removed by garbage collector.
 
 That comes at the cost of not having support for `clear`, `size`, `keys`, `values`...