Insert Git Credentials using Jenkins Pipeline Script

gistfile1.txt

Suppose you want to inject a credential into a Pipeline script.
The cloudbees note does not include Pipeline script examples.
https://support.cloudbees.com/hc/en-us/articles/203802500-Injecting-Secrets-into-Jenkins-Build-Jobs

The Jenkins Pipeline Docs' description of the `git push`method doesn't have an example using injected credentials. 
(https://jenkins.io/doc/pipeline/examples/#push-git-repo)

The Snippet generator is helpful, but not not if you try to follow the instructions at:
https://wiki.jenkins-ci.org/display/JENKINS/Credentials+Binding+Plugin

If you have associated a credential with your Git repo, use the Snippet Generator to select the plain `Git` option and it will return a snippet with this gem.

```java
stage('Checkout') {
       git branch: 'lts-1.532', credentialsId: '82aa2d26-ef4b-4a6a-a05f-2e1090b9ce17', url: 'git@github.com:jenkinsci/maven-plugin.git'
   }
```

Note that the `credentialsID` is a cryptic string and not at all like the display name I originally expected.