Add a conflict with squizlabs/php_codesniffer version 4 (see #19)

Description
-----------

`squizlabs/php_codesniffer` has been released in version 4.0.0, but is incompatible with `symplify/easy-coding-standard` at the moment.

See easy-coding-standard/easy-coding-standard#299.

Commits
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ed604cb Add conflict with squizlabs/php_codesniffer 4.x versions

Author: bytehead

composer.json

@@ -19,6 +19,9 @@
         "contao/rector": "^1.2",
         "phpunit/phpunit": "^11.5"
     },
+    "conflict": {
+        "squizlabs/php_codesniffer": ">=4.0.0"
+    },
     "autoload": {
         "psr-4": {
             "Contao\\EasyCodingStandard\\": "src/"