ci: prebuildify for linux-arm64

Uses https://github.com/pguyot/arm-runner-action to have a native
arm64 linux environment to compile the prebuild for linux-arm64.

prebuildify-cross would be easier, but unfortunately does not work
due to the xtst headers not present in the docker images that
prebuildify-cross uses internally.

.github/workflows/ci.yml

@@ -21,6 +21,9 @@ jobs:
           - os: ubuntu-20.04
             arch: x64
             build-group: linux-x64
+          - os: ubuntu-20.04
+            arch: x64
+            build-group: linux-arm64
           - os: macos-11
             arch: x64
             build-group: darwin-universal
@@ -38,17 +41,32 @@ jobs:
       with:
         node-version: '16'
         architecture: ${{ matrix.arch }}
-    - name: Install linux dependencies
-      if: startsWith(matrix.os, 'ubuntu')
+    - name: Prebuildify for linux-arm64
+      if: ${{ matrix.build-group == 'linux-arm64' }}
+      uses: pguyot/arm-runner-action@v2
+      with:
+        base_image: raspios_lite_arm64:latest
+        image_additional_mb: 5000
+        copy_artifact_path: prebuilds
+        commands: |
+            curl -fsSL https://deb.nodesource.com/setup_16.x | bash -
+            apt-get -y install nodejs libxtst-dev libpng++-dev
+            npm ci
+            npm run prebuild-$BUILD_GROUP
+    - name: Install linux x64 dependencies
+      if: ${{ matrix.build-group == 'linux-x64' }}
       run: sudo apt-get install libxtst-dev libpng++-dev
     - run: npm ci
+      if: ${{ matrix.build-group != 'linux-arm64' }}
     - name: Prebuildify
+      if: ${{ matrix.build-group != 'linux-arm64' }}
       run: npm run prebuild-$BUILD_GROUP
       shell: bash
     - uses: actions/upload-artifact@v3
       with:
         name: prebuilds
         path: prebuilds/
+        if-no-files-found: error
   publish:
     name: Publish to npm
     if: github.event_name == 'push' && github.ref == 'refs/heads/master'

package.json

@@ -13,6 +13,7 @@
     "prebuild": "prebuildify -t 16.0.0 --napi --strip",
     "prebuild-darwin-universal": "prebuildify -t 16.0.0 --napi --strip --arch x64+arm64",
     "prebuild-linux-x64": "prebuildify -t 16.0.0 --napi --strip",
+    "prebuild-linux-arm64": "prebuildify -t 16.0.0 --napi --strip",
     "prebuild-win32-x86": "prebuildify -t 16.0.0 --napi --strip",
     "prebuild-win32-x64": "prebuildify -t 16.0.0 --napi --strip"
   },