Build/Test Tools: Update third-party GitHub Actions to latest versions.

Updated actions:
- `actions/cache`
- `actions/github-script`
- `actions/setup-node`
- `bubkoo/welcome-action`
- `shivammathur/setup-php`
- `slackapi/slack-github-action`

See #55652.

git-svn-id: https://develop.svn.wordpress.org/trunk@53940 602fd350-edb4-49c9-b593-d223f7449a82

.github/workflows/php-compatibility.yml

@@ -62,7 +62,7 @@ jobs:
         uses: actions/checkout@2541b1294d2704b0964813337f33b291d3f8596b # v3.0.2
 
       - name: Set up PHP
-        uses: shivammathur/setup-php@3eda58347216592f618bb1dff277810b6698e4ca # v2.19.1
+        uses: shivammathur/setup-php@e04e1d97f0c0481c6e1ba40f8a538454fe5d7709 # v2.21.2
         with:
           php-version: '7.4'
           coverage: none
@@ -80,7 +80,7 @@ jobs:
         run: echo "::set-output name=date::$(/bin/date -u --date='last Mon' "+%F")"
 
       - name: Cache PHP compatibility scan cache
-        uses: actions/cache@c3f1317a9e7b1ef106c153ac8c0f00fed3ddbc0d # v3.0.4
+        uses: actions/cache@fd5de65bc895cf536527842281bea11763fefd77 # v3.0.8
         with:
           path: .cache/phpcompat.json
           key: ${{ runner.os }}-date-${{ steps.get-date.outputs.date }}-phpcompat-cache-${{ hashFiles('**/composer.json', 'phpcompat.xml.dist') }}