Remove operating system comments (#1447)

Closes #1050

Author: kotp

.github/workflows/exercise-tests.yml

@@ -16,8 +16,6 @@ jobs:
       matrix:
         os:
           - ubuntu-20.04
-          # - windows-latest
-          # - macOS-latest
         ruby-version: [2.6, 2.7, 3.0]
 
     steps: