Build Scalatra docs on GitHub Actions

• https://scalatra.github.io/scalatra-docbuild/
• https://scalatra.github.io/scalatra-docbuild/apidocs/2.5/org/scalatra/
• https://scalatra.github.io/scalatra-docbuild/apidocs/2.4/org/scalatra/
• https://scalatra.github.io/scalatra-docbuild/apidocs/2.3/org/scalatra/

Docs	Repo	Branch	Built with
Site	https://github.com/scalatra/scalatra-website	master	Hugo
API v2.5.x	https://github.com/scalatra/scalatra	2.5.x	sbt-unidoc
API v2.4.x	https://github.com/scalatra/scalatra	2.4.x	sbt-unidoc
API v2.3.x	https://github.com/scalatra/scalatra	2.3.x	sbt-unidoc

Options to trigger a build:

• Push a dummy change to branch master
• Invoke GitHub Actions https://github.com/scalatra/scalatra-docbuild/actions

TODO

• trigger build for push to branch master on repo scalatra-website
• remove || true for hugo build