Specify a different version of sbt

Author: liufengyun

.appveyor.yml

@@ -1,5 +1,5 @@
 version: '{build}'
-os: Windows Server 2012
+image: Visual Studio 2019
 environment:
   global:
     NODEJS_VERSION: "12"
@@ -8,7 +8,7 @@ matrix:
 
 init:
   - ps: Install-Product node $env:NODEJS_VERSION
-  - cmd: choco install sbt
+  - cmd: choco install sbt --version 1.3.12
   - cmd: refreshenv
   - cmd: SET "SBT_OPTS=-Xmx4g -Xms4m"
 build_script: