Chore(deps): Bump actions/checkout from 3.5.3 to 4.1.1

Bumps [actions/checkout](https://github.com/actions/checkout) from 3.5.3 to 4.1.1.
- [Release notes](https://github.com/actions/checkout/releases)
- [Commits](https://github.com/actions/checkout/compare/v3.5.3...v4.1.1)

---
updated-dependencies:
- dependency-name: actions/checkout
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <support@github.com>

.github/workflows/integration.yml

@@ -71,7 +71,7 @@ jobs:
           path: apps/${{ env.APP_NAME }}
 
       -   name: Checkout activity
-          uses: actions/checkout@c85c95e3d7251135ab7dc9ce3241c5835cc595a9 # v3.5.3
+          uses: actions/checkout@b4ffde65f46336ab88eb53be808477a3936bae11 # v4.1.1
           with:
               repository: nextcloud/activity
               ref: ${{ matrix.server-versions }}