Add support for PHP 8.4

- Bump dev deps
- Add BC Checker to CI
- Ignore platform reqs

Signed-off-by: George Steel <george@net-glue.co.uk>

.laminas-ci.json

@@ -1,2 +1,6 @@
 {
+    "ignore_php_platform_requirements": {
+        "8.4": true
+    },
+    "backwardCompatibilityCheck": true
 }

composer.json

@@ -35,15 +35,15 @@
         }
     },
     "require": {
-        "php": "~8.1.0 || ~8.2.0 || ~8.3.0",
+        "php": "~8.1.0 || ~8.2.0 || ~8.3.0 || ~8.4.0",
         "mezzio/mezzio-session": "^1.0",
         "psr/http-server-middleware": "^1.0"
     },
     "require-dev": {
         "laminas/laminas-coding-standard": "~2.5.0",
-        "phpunit/phpunit": "^10.2.2",
+        "phpunit/phpunit": "^10.5.36",
         "psalm/plugin-phpunit": "^0.19.0",
-        "vimeo/psalm": "^5.13.1"
+        "vimeo/psalm": "^5.26.1"
     },
     "autoload": {
         "psr-4": {