Update snapshot.yml

Author: shuzijun

.github/workflows/snapshot.yml

@@ -14,7 +14,7 @@ jobs:
       uses: actions/checkout@v2
 
     - name: Set LD_VERSION
-      run: echo ::set-env name=LD_VERSION::0.0
+      run: echo "LD_VERSION=0.0" >> $GITHUB_ENV
 
     - name: Set up JDK 1.8
       uses: actions/setup-java@v1