Fix warning `key` is undefined on project page (#5876)

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CHANGELOG.md

@@ -20,6 +20,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Fixed
 - An invalid project/org handling in webhooks (<https://github.com/opencv/cvat/pull/5707>)
+- Warning `key` is undefined on project page (<https://github.com/opencv/cvat/pull/5876>)
 
 ### Security
 - TDB

cvat-ui/src/components/projects-page/actions-menu.tsx

@@ -52,6 +52,7 @@ export default function ProjectActionsMenuComponent(props: Props): JSX.Element {
                 Import dataset
             </Menu.Item>
             <Menu.Item
+                key='backup-project'
                 disabled={exportBackupIsActive}
                 onClick={() => dispatch(exportActions.openExportBackupModal(projectInstance))}
                 icon={exportBackupIsActive && <LoadingOutlined id='cvat-export-project-loading' />}