build(deps): bump the actions-core group across 1 directory with 2 updates

Bumps the actions-core group with 2 updates in the / directory: [actions/checkout](https://github.com/actions/checkout) and [actions/setup-node](https://github.com/actions/setup-node).


Updates `actions/checkout` from 4 to 6
- [Release notes](https://github.com/actions/checkout/releases)
- [Changelog](https://github.com/actions/checkout/blob/main/CHANGELOG.md)
- [Commits](actions/checkout@v4...v6)

Updates `actions/setup-node` from 4 to 6
- [Release notes](https://github.com/actions/setup-node/releases)
- [Commits](actions/setup-node@v4...v6)

---
updated-dependencies:
- dependency-name: actions/checkout
  dependency-version: '6'
  dependency-type: direct:production
  update-type: version-update:semver-major
  dependency-group: actions-core
- dependency-name: actions/setup-node
  dependency-version: '6'
  dependency-type: direct:production
  update-type: version-update:semver-major
  dependency-group: actions-core
...

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

Author: dependabot[bot]

.github/workflows/backfill-previews.yml

@@ -42,11 +42,11 @@ jobs:
     environment: production
     timeout-minutes: 10
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
       - uses: pnpm/action-setup@v4
         with:
           version: 9
-      - uses: actions/setup-node@v4
+      - uses: actions/setup-node@v6
         with:
           node-version: 22
           cache: pnpm

.github/workflows/deploy.yml

@@ -17,11 +17,11 @@ jobs:
     environment: production
     timeout-minutes: 20
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
       - uses: pnpm/action-setup@v4
         with:
           version: 9
-      - uses: actions/setup-node@v4
+      - uses: actions/setup-node@v6
         with:
           node-version: 22
           cache: pnpm