minor #3628 Add missing use in custom field example (matthieuleorat)
minor #3628 Add missing use in custom field example (matthieuleorat)

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

Discussion
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Add missing use in custom field example

Add use statement is missing from the exemple "Creating Custom Fields"

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Commits
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6073764c Add missing use in custom field example

javiereguiluz/EasyAdminBundle,javiereguiluz/EasyAdminBundle