minor #14766 language tweak (tacman)

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

Discussion
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language tweak

"At last" means after a delay, lastly is just the last thing on the list.

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Commits
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978492d language tweak

Author: xabbuh

components/property_access.rst

@@ -223,7 +223,7 @@ The ``getValue()`` method can also use the magic ``__get()`` method::
 Magic ``__call()`` Method
 ~~~~~~~~~~~~~~~~~~~~~~~~~
 
-At last, ``getValue()`` can use the magic ``__call()`` method, but you need to
+Lastly, ``getValue()`` can use the magic ``__call()`` method, but you need to
 enable this feature by using :class:`Symfony\\Component\\PropertyAccess\\PropertyAccessorBuilder`::
 
     // ...