formatting fix for validation

Author: jeff-allen-mongo

source/validation.txt

@@ -153,8 +153,8 @@ Using this validation, *one* of the following must be true:
 - The ``phone`` field must be BSON type string,
 
 - The ``email`` field must match the
-   :manual:`regex </reference/operator/query/regex/>`
-   ``/@mongodb\.com$/``, or
+  :manual:`regex </reference/operator/query/regex/>`
+  ``/@mongodb\.com$/``, or
 
 - The ``status`` field must be either ``Unknown`` or ``Incomplete``.