Bump actions/upload-artifact from 2 to 3 (#3047)

Bumps [actions/upload-artifact](https://github.com/actions/upload-artifact) from 2 to 3.
- [Release notes](https://github.com/actions/upload-artifact/releases)
- [Commits](actions/upload-artifact@v2...v3)

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

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

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

.github/workflows/build-installer.yml

@@ -52,7 +52,7 @@ jobs:
       - name: Create installer
         run: makensis.exe ${{ github.workspace }}/installer/windows/microk8s.nsi
       - name: Upload installer
-        uses: actions/upload-artifact@v2
+        uses: actions/upload-artifact@v3
         with:
           name: Windows installer
           path: ${{ github.workspace }}/installer/windows/microk8s-installer.exe

.github/workflows/build-snap.yml

@@ -28,7 +28,7 @@ jobs:
           sg lxd -c 'snapcraft --use-lxd'
           sudo mv microk8s*.snap microk8s.snap
       - name: Uploading snap
-        uses: actions/upload-artifact@v1
+        uses: actions/upload-artifact@v3
         with:
           name: microk8s.snap
           path: microk8s.snap