Bump actions/download-artifact from 6 to 7

Bumps [actions/download-artifact](https://github.com/actions/download-artifact) from 6 to 7.
- [Release notes](https://github.com/actions/download-artifact/releases)
- [Commits](https://github.com/actions/download-artifact/compare/v6...v7)

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

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

.github/workflows/github.yml

@@ -595,7 +595,7 @@ jobs:
         PULL_REQUEST: ${{ github.event.pull_request.number }}
 
     - name: Download Artifact
-      uses: actions/download-artifact@v6
+      uses: actions/download-artifact@v7
       with:
         name: ${{ env.VCMI_PACKAGE_FILE_NAME }} - ${{ matrix.platform }}
         path: ${{github.workspace}}/artifact
@@ -700,7 +700,7 @@ jobs:
 
       - name: Download all partial JSON artifacts
         continue-on-error: true
-        uses: actions/download-artifact@v6
+        uses: actions/download-artifact@v7
         with:
           pattern: partial-json-*
           merge-multiple: true