Comment out PHP version 8.1 in build workflow

Closes crazywhalecc/static-php-cli#1059

Author: crazywhalecc

.github/workflows/build-php-unix.yml

@@ -13,7 +13,7 @@ jobs:
       fail-fast: false
       matrix:
         php-version:
-          - "8.1"
+          # - "8.1"
           - "8.2"
           - "8.3"
           - "8.4"