[Docs] Add missing import in custom App code example (#10047)
[Docs] Add missing import in custom App code example (#10047)

* Updated comment

* Removed unexpected word

* Update custom-app.md

* Update custom-app.md

Co-authored-by: Joe Haddad <4e0ba6b7cd003e26bd2c43baef51e423886a04cd@gmail.com>

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