test lts instead of 1.6

Author: klamike

.github/workflows/ci.yml

@@ -17,7 +17,7 @@ jobs:
       fail-fast: false
       matrix:
         include:
-          - version: '1.6'
+          - version: 'lts'
             os: ubuntu-latest
             arch: x64
           - version: '1'