Test on PHP 8.4

Author: BenMorel

.github/workflows/ci.yml

@@ -3,8 +3,8 @@ name: CI
 on: [push, pull_request]
 
 env:
-  PSALM_PHP_VERSION: "8.3"
-  COVERAGE_PHP_VERSION: "8.3"
+  PSALM_PHP_VERSION: "8.4"
+  COVERAGE_PHP_VERSION: "8.4"
 
 jobs:
   psalm:
@@ -37,6 +37,7 @@ jobs:
           - "8.1"
           - "8.2"
           - "8.3"
+          - "8.4"
         deps:
           - "highest"
         include: