Jenkinsfile: check scm woes with the GitHub Org Folders

Jenkinsfile

#!groovy

node {
  stage('desired') {
    // This is what I'd like to be able to do... Though there are lots of other extenions that are useful, like
    // CleanBeforeCheckout and PruneStaleBranch
    // Don't forget submodule configuration!
    scm.extenions = scm.extensions + [[$class: 'CloneOption', noTags: true, reference: '', shallow: true]]
    checkout scm
  }

  stage('alternate-desired') {
    // Use a CPS library to build a _base_ duplicate SCM object. It would have userRemoteConfigs and branches
    // already setup.
    myScm = buildScm()
    myScm.extensions = scm.extensions + [[$class: 'CloneOption', noTags: true, reference: '', shallow: true]]
    checkout myScm
  }

  stage('what-i-have-to-do') {
    // this is how I currently work around the problem.
    checkout(
      [
      $class: 'GitSCM',
      userRemoteConfigs: [[credentialsId: 'my-credentials-id', url: 'hard-coded-git-url-breaks-forking']],
      branches: [[name: '*/$BRANCH_NAME']], // I don't like specifying the branch this way.
      extensions: [
      [$class: 'AuthorInChangelog'],
      [$class: 'CheckoutOption', timeout: 10],
      [$class: 'CleanBeforeCheckout'],
      [$class: 'CloneOption', depth: 3, honorRefspec: true, noTags: true, reference: '', shallow: true, timeout: 3]
      ]
      ]
    )
  }
}