Update main.yml

.github/workflows/main.yml

@@ -1,6 +1,12 @@
 name: CI
 
-on: [push]
+on:
+  push:
+    tags:
+    - 'v*'
+    branches:
+    - master
+    - next
 
 jobs:
   build:
@@ -11,7 +17,7 @@ jobs:
     - uses: actions/checkout@v2
     - name: docker build
       run: |
-        export DOCKER_CLI_EXPERIMENTAL=enabled
+        env
         export ARCH=$([ $(uname -m) = "x86_64" ] && echo "amd64" || echo "arm64")
         mkdir -p ~/.docker/cli-plugins/
         wget -qO ~/.docker/cli-plugins/docker-buildx https://github.com/docker/buildx/releases/download/v0.3.1/buildx-v0.3.1.linux-${ARCH}
@@ -21,4 +27,5 @@ jobs:
         docker run --rm --privileged multiarch/qemu-user-static --reset -p yes
         docker buildx create --name xbuilder --use
         docker buildx inspect --bootstrap
-        
+      env:
+        DOCKER_CLI_EXPERIMENTAL: enabled