Upgrade actions/upload-artifact from v2 to v3

v2 uses Node.js 12.x which is EOL.

Signed-off-by: Kazuyoshi Kato <katokazu@amazon.com>

.github/workflows/release.yml

@@ -46,7 +46,7 @@ jobs:
         working-directory: src/github.com/containerd/containerd
 
       - name: Save release notes
-        uses: actions/upload-artifact@v2
+        uses: actions/upload-artifact@v3
         with:
           name: containerd-release-notes
           path: src/github.com/containerd/containerd/release-notes.md
@@ -116,7 +116,7 @@ jobs:
         env:
           PLATFORM: ${{ matrix.dockerfile-platform }}
       - name: Save Artifacts
-        uses: actions/upload-artifact@v2
+        uses: actions/upload-artifact@v3
         with:
           name: release-tars-${{env.PLATFORM_CLEAN}}
           path: src/github.com/containerd/containerd/releases/*.tar.gz*