minor #3568 Update checkbox_compound.rst.inc (joshuaadickerson)

This PR was merged into the 2.3 branch.

Discussion
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Update checkbox_compound.rst.inc

Sorry for the quick PRs in succession. Blame it on craue in #symfony

Commits
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4490dab Update checkbox_compound.rst.inc

Author: weaverryan

reference/forms/types/options/checkbox_compound.rst.inc

@@ -4,5 +4,5 @@ compound
 **type**: ``boolean`` **default**: ``false``
 
 This option specifies if a form is compound. As it's not the
-case for checkbox, by default the value is overriden with
+case for checkbox, by default the value is overridden with
 ``false`` value.