feat: allow for custamizable detailsURL in withChecks

[esatterwhite]

When using the withChecks wrapper the details url always points to the jenkins ui for the build. in cases where jenkins is behind a comany firewall or other network boundaries, this can be a bit frustrating for people outside the firewall on public facing repositories. Having the details url point to something that is accessible is very useful, but it is only possible with publishChecks.

This aims to add the same functionality through the withChecks step.

Resolves: #328

Testing done

• I stood up a local instance of jenkins w/ this plugin
• I created a github repo
• added a Jenkinsfile
• allowed the job to run against a gitub repo and publish checks with a custom url

pipeline {
    agent any

    stages {
        stage('Hello') {
            steps {
                withChecks(
                    name: 'test',
                    detailsURL: 'http://codedependant.net'
                ) {
                    echo 'Hello World'
                    echo 'ls -alh'
                }
            }
        }
    }
}

Reference build: https://github.com/esatterwhite/jenkins-checks-test/pull/1/checks?check_run_id=77236702409

It also still works with the original function signature syntax

withChecks('test') {
// more steps
}

Reference build: https://github.com/esatterwhite/jenkins-checks-test/pull/2/checks?check_run_id=77240137433

Submitter checklist

• Make sure you are opening from a topic/feature/bugfix branch (right side) and not your main branch!
• Ensure that the pull request title represents the desired changelog entry
• Please describe what you did
• Link to relevant issues in GitHub or Jira
• Link to relevant pull requests, esp. upstream and downstream changes
• Ensure you have provided tests that demonstrate the feature works or the issue is fixed

[timja]

not tested fully end 2 end but I've checked the UI and it looks fine.

Few minor comments.

[timja]

don't use the empty string, just return null I think

[esatterwhite]

@timja
Should defaultURL default to null everywhere? I think I'm defaulting it to an empty string

[timja]

yeah default to null