21.0.0

What's Changed

• Remove v15-branch from checks by @mikelittle in #572
• Remove final references to chassis by @mikelittle in #573
• Reference latest Travis module by @mikelittle in #574
• Update travis modules reference by @mikelittle in #575
• Reformat and correct docs files after linting by @mikelittle in #577
• UpdatePHP compatibility chart for PHP 8.3 by @mikelittle in #578
• Upgrading Guide for Altis v20 by @mikelittle in #579
• Updated some wording. AddNode.js section. by @mikelittle in #582
• Update dependabot for v20 release by @mikelittle in #581
• Docs: Remove duplicated Node.js section from v20 upgrade guide by @kadamwhite in #584
• Update script to reference new module commit. by @mikelittle in #586
• Fixes spelling of Elasticsearch. by @mikelittle in #588
• [Backport v21-branch] Add v21 upgrade guide by @hm-backport in #590

Full Changelog: 19.0.0...21.0.0