Currently on a PR all are built, and if any one fails the CI fails, even if the failure is in a plugin that is not the plugin the PR changes.
Possible implementations:
1. the CI setup uses git to find the plugin directories that the PR touches and only builds those plugins, and 2. if the PR title contains (as regex) `[[a-zA-Z0-9_]+(,[a-zA-Z0-9_]+)*]` build the plugins named (for when something outside the plugin directory is changed, the m4 for example)