minor symfony#9558 add missing ";" (TomasVotruba)

This PR was submitted for the 4.0 branch but it was merged into the 3.4 branch instead (closes symfony#9558).

Discussion
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add missing ";"

Commits
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21e3daa add missing ";"

Author: javiereguiluz

components/cache/psr6_psr16_adapters.rst

@@ -37,7 +37,7 @@ instead. No problem! The Cache component provides the
 this use-case::
 
     use Symfony\Component\Cache\Simple\FilesystemCache;
-    use Symfony\Component\Cache\Adapter\SimpleCacheAdapter
+    use Symfony\Component\Cache\Adapter\SimpleCacheAdapter;
 
     // the PSR-16 cache object that you want to use
     $psr16Cache = new FilesystemCache();