I was working on a failed script, and got stuck with this.
Please advise me on fixing this POST call - with JSON builder. 
Reference: https://docs.groovy-lang.org/latest/html/documentation/core-domain-specific-languages.html#_jsonbuilder
Code: 
 
// Set up the JSON body for the POST request
def jsonBody = new JsonBuilder()
log.warn("jsonBody is : " + jsonBody)
log.warn(jsonBody.content)
jsonBody{ 
 {
      globalId 'appId=e9530ad1-eea0-b65d-0d2a2fd1e13b&issueId=${issue.id}'
      application {
          type 'com.atlassian.jira'
          name 'JIRA DEV'
      }
    relationship 'relates to'
    object{
      title 'Linked Issues'
      summary '${issue.summary}'
          }
        } 
      }
log.warn("jsonBody is : " + jsonBody