Merge commit '6e1229e4' as '.Build/gitlab-ci'

.Build/gitlab-ci/README.md

.Build/gitlab-ci/extension-gitlab-ci.yml

.Build/gitlab-ci/php-cs-fixer/Extension.php

.Build/gitlab-ci/php-cs-fixer/Project.php

.Build/gitlab-ci/project-gitlab-ci.yml

.Build/gitlab-ci/typo3-rector/Extension.php

.Build/gitlab-ci/typo3-rector/Project.php

.Build/gitlab-ci/typoscript-lint/Extension.yml

.Build/gitlab-ci/typoscript-lint/Project.yml