minor #11442 Missing square bracket (Webcretaire)

This PR was merged into the 4.2 branch.

Discussion
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Missing square bracket

Typo in cache documentation regarding tags

Commits
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665ca3e Missing square bracket

Author: javiereguiluz

components/cache.rst

@@ -116,7 +116,7 @@ recompute::
     $beta = 1.0;
     $value = $cache->get('my_cache_key', function (ItemInterface $item) {
         $item->expiresAfter(3600);
-        $item->tag(['tag_0', 'tag_1');
+        $item->tag(['tag_0', 'tag_1']);
 
         return '...';
     }, $beta);