minor #3972 Improve doc - custom action (seb-jean)
minor #3972 Improve doc - custom action (seb-jean)

This PR was merged into the 3.0.x-dev branch.

Discussion
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Improve doc - custom action

Fix #3662

Commits
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9b6675fb Update actions.rst

javiereguiluz/EasyAdminBundle,javiereguiluz/EasyAdminBundle