minor #14537 [Lock] Fix broken configuration block (HypeMC)

This PR was merged into the 4.4 branch.

Discussion
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[Lock] Fix broken configuration block

The formatting is broken: https://symfony.com/doc/4.4/lock.html#named-lock

![image](https://user-images.githubusercontent.com/2445045/99098189-ef20cd00-25d8-11eb-9ad9-458022cdf9c2.png)

Commits
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1aa619a Fix broken configuration block

Author: javiereguiluz

lock.rst

@@ -223,7 +223,7 @@ Named Lock
 ----------
 
 If the application needs different kind of Stores alongside each other, Symfony
-provides :ref:`named lock <reference-lock-resources-name>`::
+provides :ref:`named lock <reference-lock-resources-name>`:
 
 .. configuration-block::