New configRoundtrip method for Cloud configuration

[sparsick]

In Jenkins plugin azure-container-plugin, there is a use case to test the correctness of the cloud configuration. The JenkinsRule has no configRoundtrip method for the cloud configuration.

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[jglick]

Looks right. To prove that the API can be (and will be) used as written, you should create a draft PR in whatever plugin calling this method. (Include the URL of this PR in the Description to create a backlink.) Look up the incremental version number of this PR (see the Checks tab) and in your draft plugin PR add to <properties> in pom.xml

<jenkins-test-harness.version>1234.vwhatever</jenkins-test-harness.version> <!-- TODO https://github.com/jenkinsci/jenkins-test-harness/pull/426 -->

If your plugin has not yet been “incrementalified” then also

mkdir .mvn
echo -Pconsume-incrementals > .mvn/maven.config
git add .mvn

[jglick]

(just awaiting downstream PR)

[sparsick]

Downstream PR is created jenkinsci/azure-container-agents-plugin#132