Add ARM64 build to Travis CI script

.travis.yml

@@ -32,3 +32,17 @@ matrix:
         draft: true
         on:
           tags: true
+    - services: docker
+      arch: arm64
+      script:
+      - docker pull alpine:latest
+      - docker run -v $TRAVIS_BUILD_DIR:/root/workdir alpine:latest /bin/sh -c "apk add bash git && cd /root/workdir && chmod +x scripts/build.alpine.release.sh && bash scripts/build.alpine.release.sh"
+      - mv subconverter_linux64.tar.gz subconverter_aarch64.tar.gz
+      deploy:
+        provider: releases
+        api_key: "$GITHUB_OAUTH_TOKEN"
+        file: "subconverter_aarch64.tar.gz"
+        skip_cleanup: true
+        draft: true
+        on:
+          tags: true