minor #11188 Add precision on the concerned fields in the Default validation group (florianbelhomme)

This PR was merged into the 3.4 branch.

Discussion
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 Add precision on the concerned fields in the Default validation group

Explicitly tells which field's constraint is in the ``Default`` validation group.

Commits
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dbda710 Add precision on the concerned fields

Author: javiereguiluz

validation/groups.rst

@@ -132,7 +132,8 @@ With this configuration, there are three validation groups:
 
 ``Default``
     Contains the constraints in the current class and all referenced classes
-    that belong to no other group.
+    that belong to no other group. Contains the constraint on the ``city``
+    field only.
 
 ``User``
     Equivalent to all constraints of the ``User`` object in the ``Default``