v4.21.0

What's Changed

• Fix release step by @wildmaples in #128
• Add gem build and push before publish by @wildmaples in #130
• Support template definition within an extension by @wildmaples in #131
• Update README.md with newer docker plugin and image by @technicalpickles in #126
• Bump version to 4.18.0 by @wildmaples in #134
• Add Extension documentation by @wildmaples in #133
• Support matrix builds by @wildmaples in #137
• Check before downloading gem by @wildmaples in #136
• Add support for blocked_state attribute in input steps by @jksmithing in #138
• Add allowed_teams attribute to block step by @nick-f in #139

New Contributors

• @nick-f made their first contribution in #139

Full Changelog: v4.17.0...v4.21.0