Test with PHP 8.6

Author: sebastianbergmann

.github/workflows/ci.yaml

@@ -174,6 +174,7 @@ jobs:
           - "8.3"
           - "8.4"
           - "8.5"
+          - "8.6"
 
     steps:
       - name: Configure Git to avoid issues with line endings
@@ -250,6 +251,7 @@ jobs:
           - "8.3"
           - "8.4"
           - "8.5"
+          - "8.6"
 
     steps:
       - name: Configure Git to avoid issues with line endings
@@ -507,6 +509,7 @@ jobs:
           - "8.3"
           - "8.4"
           - "8.5"
+          - "8.6"
 
     steps:
       - name: Checkout