chore: migrate jenkins job to k8s agent pipeline (#1251)

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### Changes

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chore: migrate jenkins job to k8s agent pipeline

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- [ ] This change adds integration test coverage
- [ ] This change has been tested on the latest version of the
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### Checklist

- [ ] I have read the [Auth0 general contribution
guidelines](https://github.com/auth0/open-source-template/blob/master/GENERAL-CONTRIBUTING.md)
- [ ] I have read the [Auth0 Code of
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Co-authored-by: Steve Hobbs <[email protected]>

Jenkinsfile

@@ -1,6 +1,11 @@
+@Library('k8sAgents') agentLibrary
+@Library('auth0') _
+
 pipeline {
   agent {
-    label 'crew-brucke'
+    kubernetes {
+      yaml defaultAgent()
+    }
   }
 
   tools {
@@ -12,14 +17,6 @@ pipeline {
   }
 
   stages {
-    stage('SharedLibs') {
-      steps {
-        library identifier: 'auth0-jenkins-pipelines-library@master', retriever: modernSCM(
-          [$class: 'GitSCMSource',
-          remote: '[email protected]:auth0/auth0-jenkins-pipelines-library.git',
-          credentialsId: 'auth0extensions-ssh-key'])
-      }
-    }
     stage('Build') {
       steps {
         sshagent(['auth0extensions-ssh-key']) {