maint: refresh ci.yml to use build.sh on all sites #865

tavultesoft.com ci.yml (see chore: additional CI tavultesoft.com#8) is simplified to use build.sh calls throughout. We should use a similar pattern on all sites to reduce maintenance overhead. (All the various workflows add significant overhead to keep in sync)

The inverted test parameters such as --no-lint could be refactored into positive parameters instead?

While we are at it, let's cleanup and centralize the container name/desc/image as well, e.g.:

readonly R_KEYMANWEB_CONTAINER_NAME=r-keymanweb-com-website
readonly R_KEYMANWEB_CONTAINER_DESC=r-keymanweb-com-app
readonly R_KEYMANWEB_IMAGE_NAME=r-keymanweb-com-website
readonly HOST_R_KEYMANWEB_COM=r.keymanweb.com.localhost

if we can keep (at least some of) the GH workflow scripts in shared-sites and deploy across to each of the other sites, that'd also be awesome?

Centralize label configuration (colours, names, available labels)