minor #15351 [Lock] Update lock.rst (mismailzai)

This PR was submitted for the 5.2 branch but it was merged into the 4.4 branch instead.

Discussion
----------

[Lock] Update lock.rst

fix typo

<!--

If your pull request fixes a BUG, use the oldest maintained branch that contains
the bug (see https://symfony.com/releases for the list of maintained branches).

If your pull request documents a NEW FEATURE, use the same Symfony branch where
the feature was introduced (and `5.x` for features of unreleased versions).

-->

Commits
-------

f0fa111 Update lock.rst

Author: javiereguiluz

components/lock.rst

@@ -474,7 +474,7 @@ PHP process is terminated::
 Reliability
 -----------
 
-The component guarantees that the same resource can't be lock twice as long as
+The component guarantees that the same resource can't be locked twice as long as
 the component is used in the following way.
 
 Remote Stores