Update github actions to address warnings

- Update github actions version for node.js 16
- Update github ::set-output usage

.github/workflows/build.yml

@@ -9,14 +9,13 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       # Set steps.os.outputs.image to the specific OS (e.g. 'ubuntu20')
-      # see https://github.com/actions/cache/issues/543
       - name: Get operating system name and version.
         id: os
-        run: echo "::set-output name=image::$ImageOS"
+        run: echo "image=$ImageOS" >>$GITHUB_OUTPUT
         shell: bash
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v3
       - name: Cache pulseaudio source
-        uses: actions/cache@v2
+        uses: actions/cache@v3
         env:
           cache-name: cache-pulseaudio-src
         with:
@@ -44,16 +43,16 @@ jobs:
     steps:
       - name: Get operating system name and version.
         id: os
-        run: echo "::set-output name=image::$ImageOS"
+        run: echo "image=$ImageOS" >>$GITHUB_OUTPUT
         shell: bash
       - name: Fetch pulseaudio sources
-        uses: actions/cache@v2
+        uses: actions/cache@v3
         env:
           cache-name: cache-pulseaudio-src
         with:
           path: ~/pulseaudio.src
           key: ${{ steps.os.outputs.image }}-build-${{ env.cache-name }}
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v3
       - run: sudo apt-get update
       - run: sudo apt-get -yq install build-essential libpulse-dev
       - run: ./bootstrap