Test on PHP 8.1

Author: ruudk

.github/workflows/build.yml

@@ -21,6 +21,7 @@ jobs:
           - "7.3"
           - "7.4"
           - "8.0"
+          - "8.1"
 
     steps:
       - name: "Checkout"
@@ -85,6 +86,7 @@ jobs:
           - "7.3"
           - "7.4"
           - "8.0"
+          - "8.1"
         dependencies:
           - "lowest"
           - "highest"
@@ -127,6 +129,7 @@ jobs:
           - "7.3"
           - "7.4"
           - "8.0"
+          - "8.1"
         dependencies:
           - "lowest"
           - "highest"