Jenkins Declarative Pipeline: Passing Variables between Stages and between script{} and "sh" blocs

gistfile1.txt

This works:

```
def something="entity"
pipeline {
  agent any
  stages {
    stage("hello") {
      steps {
          
        script {
          echo something
          something = "wintermute";
        }
        
        script {
            
            echo "Retrieving value transported between stages" + something
            AFW_MID=something     
        }

      }
    }
    
    stage("goodbye") {
      steps {
        script {
            env.mid = AFW_MID
            echo "Getting value from last stage: ...  "
            echo mid
             echo "Done getting value from last stage: ...  "
        }
        
        //Single quote multiline shell command bloc:
        sh '''
        echo "Getting pipeline env variable value with interpolation " $mid
        '''
    
      }
    }
  }
}
```

Full issue description: https://github.com/jenkinsci/configuration-as-code-plugin/issues/2536