Bump actions/checkout in /.github/workflows in the actions group (#536)

Bumps the actions group in /.github/workflows with 1 update: [actions/checkout](https://github.com/actions/checkout).


Updates `actions/checkout` from 6.0.3 to 7.0.0
- [Release notes](https://github.com/actions/checkout/releases)
- [Changelog](https://github.com/actions/checkout/blob/main/CHANGELOG.md)
- [Commits](https://github.com/actions/checkout/compare/df4cb1c069e1874edd31b4311f1884172cec0e10...9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0)

---
updated-dependencies:
- dependency-name: actions/checkout
  dependency-version: 7.0.0
  dependency-type: direct:production
  update-type: version-update:semver-major
  dependency-group: actions
...

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

.github/workflows/run-integration-tests-namespace-optional.yml

@@ -21,7 +21,7 @@ jobs:
          NAMESPACE1: integration-test-namespace1-${{ github.run_id }}
          NAMESPACE2: integration-test-namespace2-${{ github.run_id }}
       steps:
-         - uses: actions/checkout@df4cb1c069e1874edd31b4311f1884172cec0e10 # v6.0.3
+         - uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7.0.0
 
          - uses: ./.github/actions/minikube-setup
            name: Setup Minikube Environment