minor #14022 Update validation.rst (xepozz)

This PR was submitted for the 5.1 branch but it was merged into the 4.4 branch instead.

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Update validation.rst

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f22c14c Update validation.rst

Author: javiereguiluz

validation.rst

@@ -119,7 +119,7 @@ following:
 .. index::
    single: Validation; Using the validator
 
-Using the ``validator`` Service
+Using the validator Service
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
 Next, to actually validate an ``Author`` object, use the ``validate()`` method