actions/checkout maybe used by Gitea, which allows installing the
server instance in a subdirectory to the service root, therefore a full
serviceUrl must be used.
Signed-off-by: You-Sheng Yang <vicamo@gmail.com>
* Adding the ability to specify the GitHub Server URL and allowing for it to differ from the Actions workflow host
* Adding tests for injecting the GitHub URL
* Addressing code review comments for PR #922
