minor #9364 Typo fix (toniperic)

This PR was submitted for the 4.0 branch but it was merged into the 3.4 branch instead (closes #9364).

Discussion
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Typo fix

Commits
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6c7d94d Typo fix

Author: javiereguiluz

components/cache/cache_pools.rst

@@ -184,10 +184,10 @@ its compatibe cache adapters (and those that do not implement ``PruneableInterfa
 silently ignored)::
 
     use Symfony\Component\Cache\Adapter\ApcuAdapter;
-    use Syfmony\Component\Cache\Adapter\ChainAdapter;
-    use Syfmony\Component\Cache\Adapter\FilesystemAdapter;
-    use Syfmony\Component\Cache\Adapter\PdoAdapter;
-    use Syfmony\Component\Cache\Adapter\PhpFilesAdapter;
+    use Symfony\Component\Cache\Adapter\ChainAdapter;
+    use Symfony\Component\Cache\Adapter\FilesystemAdapter;
+    use Symfony\Component\Cache\Adapter\PdoAdapter;
+    use Symfony\Component\Cache\Adapter\PhpFilesAdapter;
 
     $cache = new ChainAdapter(array(
         new ApcuAdapter(),       // does NOT implement PruneableInterface