fix(php): drop unused/vulnerable dev tooling from client template

squizlabs/php_codesniffer ~2.6 only resolves to versions flagged by
Composer's security-advisory audit, breaking `composer install` in CI.
Neither it nor friendsofphp/php-cs-fixer is invoked anywhere in the
PHP client's CI pipeline, and the .php_cs config that would have
driven the fixer was already orphaned (wrong filename to be picked up
by the generator, and using a Config::create() API removed in
php-cs-fixer 3.x). Remove both as dead weight.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

Author: jablan

openapi-generator/templates/php/.gitattributes

@@ -4,6 +4,5 @@
 .gitattributes export-ignore
 .gitignore export-ignore
 .openapi-generator-ignore export-ignore
-.php_cs export-ignore
 git_push.sh export-ignore
 phpunit.xml.dist export-ignore

openapi-generator/templates/php/.php_cs

@@ -30,9 +30,7 @@
         "guzzlehttp/guzzle": "^7.9"
     },
     "require-dev": {
-        "phpunit/phpunit": "^12.1",
-        "squizlabs/php_codesniffer": "~2.6",
-        "friendsofphp/php-cs-fixer": "~2.12"
+        "phpunit/phpunit": "^12.1"
     },
     "autoload": {
         "psr-4": { "{{escapedInvokerPackage}}\\" : "{{srcBasePath}}/" }