chore(deps): bump actions/upload-artifact from 4 to 7 (#9770)

Bumps [actions/upload-artifact](https://github.com/actions/upload-artifact) from 4 to 7.
- [Release notes](https://github.com/actions/upload-artifact/releases)
- [Commits](actions/upload-artifact@v4...v7)

---
updated-dependencies:
- dependency-name: actions/upload-artifact
  dependency-version: '7'
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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

Author: dependabot[bot]

.github/workflows/backend_build.yml

@@ -237,7 +237,7 @@ jobs:
       # platform-tag (single-arch entries) keeps the artifact name non-trailing.
       - name: Upload digest artifact
         if: github.event_name != 'pull_request'
-        uses: actions/upload-artifact@v4
+        uses: actions/upload-artifact@v7
         with:
           name: digests${{ inputs.tag-suffix }}--${{ inputs.platform-tag || 'single' }}
           path: /tmp/digests/*

.github/workflows/image_build.yml

@@ -187,7 +187,7 @@ jobs:
 
       - name: Upload digest artifact
         if: github.event_name != 'pull_request'
-        uses: actions/upload-artifact@v4
+        uses: actions/upload-artifact@v7
         with:
           name: digests-localai${{ inputs.tag-suffix == '' && '-core' || inputs.tag-suffix }}-${{ inputs.platform-tag }}
           path: /tmp/digests/*