[JENKINS-63284] add note to README about pipelines support
[JENKINS-63284] add note to README about pipelines support

biouno/uno-choice-plugin,imoutsatsos/uno-choice-plugin,jenkinsci/active-choices-plugin,biouno/uno-choice-plugin,jenkinsci/active-choices-plugin,imoutsatsos/uno-choice-plugin,jenkinsci/active-choices-plugin,jenkinsci/active-choices-plugin,biouno/uno-choice-plugin,imoutsatsos/uno-choice-plugin,biouno/uno-choice-plugin,imoutsatsos/uno-choice-plugin