Update official GitHub Actions to v4

Author: jackwakefield

.github/workflows/build.yml

@@ -39,7 +39,7 @@ jobs:
         run: |
           echo "PHP_API=$(php-config --phpapi)" >> $GITHUB_ENV
       - name: Checkout
-        uses: actions/checkout@v2
+        uses: actions/checkout@v4
       - name: Build
         run: |
           phpize
@@ -48,7 +48,7 @@ jobs:
           make
           make test REPORT_EXIT_STATUS=1 NO_INTERACTION=1 TESTS="--show-all"
       - name: Save artifact
-        uses: actions/upload-artifact@v2
+        uses: actions/upload-artifact@v4
         with:
           name: fakerandom_${{ env.PHP_API }}.so
           path: modules/fakerandom.so
@@ -60,7 +60,7 @@ jobs:
     needs: build
     steps:
       - name: Download artifacts
-        uses: actions/download-artifact@v2
+        uses: actions/download-artifact@v4
       - name: Combine artifacts
         run: |
           mkdir -p output