Add test targets of Ruby

Signed-off-by: kentarohorie <[email protected]>

Author: kentarohorie

.github/workflows/linux.yml

@@ -14,6 +14,8 @@ jobs:
           - '2.6'
           - '2.7'
           - '3.0'
+          - '3.1'
+          - '3.2'
         os:
           - ubuntu-latest
     name: Ruby ${{ matrix.ruby }} unit testing on ${{ matrix.os }}