Bump actions/download-artifact from 2 to 4.1.7 in /.github/workflows

Bumps [actions/download-artifact](https://github.com/actions/download-artifact) from 2 to 4.1.7.
- [Release notes](https://github.com/actions/download-artifact/releases)
- [Commits](actions/download-artifact@v2...v4.1.7)

---
updated-dependencies:
- dependency-name: actions/download-artifact
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <[email protected]>

.github/workflows/build.yml

@@ -115,7 +115,7 @@ jobs:
           ref: "mainline"
           fetch-depth: 1
       - name: "fetch server artifact"
-        uses: "actions/download-artifact@v2"
+        uses: "actions/download-artifact@v4.1.7"
         with:
           name: "ttmb-server-${{needs.build.outputs.version}}"
           path: "server-artifact"
@@ -154,12 +154,12 @@ jobs:
           ref: "mainline"
           fetch-depth: 1
       - name: "fetch server artifact"
-        uses: "actions/download-artifact@v2"
+        uses: "actions/download-artifact@v4.1.7"
         with:
           name: "ttmb-server-${{needs.build.outputs.version}}"
           path: "server-artifact"
       - name: "fetch client artifact"
-        uses: "actions/download-artifact@v2"
+        uses: "actions/download-artifact@v4.1.7"
         with:
           name: "ttmb-client-${{needs.build.outputs.version}}"
           path: "client-artifact"