经过调查，我发现这个解决方案将Mercurialscm更改为GitScm，其中包含存储库url的信息，以及1个管道的凭据，并且我可以将其扩展到管道列表

import hudson.plugins.git.*;

def it = Jenkins.instance.getItemByFullName("test-pipeline-scm")
def definition = it.getDefinition() 
String scriptPath = definition.getScriptPath()
String url =  definition.getScm().getSource()
String credentials = definition.getScm().getCredentialsId()
def scm = new GitSCM(GitSCM.createRepoList(url, credentials),
                Collections.singletonList(new BranchSpec("*/master")),
                false, Collections.<SubmoduleConfig>emptyList(),
                null, null, Collections.emptyList())
def newDefinition = new org.jenkinsci.plugins.workflow.cps.CpsScmFlowDefinition(scm, scriptPath)
it.definition = newDefinition
it.save()