Update CI version from 1.6 to 1.12

Author: shawn-tao01

.github/workflows/CI.yml

@@ -21,7 +21,7 @@ jobs:
       fail-fast: false
       matrix:
         version:
-          - '1.6'
+          - '1.12'
           - 'nightly'
         os:
           - ubuntu-latest