Merge branch 'renovate/composer-2.x' into 'master'

Update composer Docker tag to v2.6.6

See merge request !210

.gitlab-ci.yml

@@ -7,7 +7,7 @@ variables:
 
 PHPstan:
   stage: test
-  image: composer:2.6.5
+  image: composer:2.6.6
   before_script:
     - composer install --ignore-platform-reqs
   script:
@@ -77,7 +77,7 @@ Webpack:
 
 Composer:
   stage: build
-  image: composer:2.6.5
+  image: composer:2.6.6
   script:
     - apk add php-cli composer php-gd php-ctype php-xml php-simplexml php-xmlwriter php-tokenizer php-session php-dom php-mysqli php-pdo_mysql
     - composer install --optimize-autoloader