Version 0.6.3

What's Changed

• .env symlink by @clemzarch in #107
• replace "?type" with "null|type" to pass new cs-fixer rule by @clemzarch in #109
• clear vendors when composer.json is not valid, by @clemzarch in #106
• delete old pipelines when building a workflow by @clemzarch in #108

Full Changelog: v0.6.2...v0.6.3