Configuring parameter of type "password" is no longer available out-of-the-box with the DSL plugin.

https://jenkinsci.github.io/job-dsl-plugin/#method/javaposse.jobdsl.dsl.jobs.WorkflowJob.parameters

Likely related to the security hardening:

https://github.com/jenkinsci/jenkins/commit/8a9a1b2f7bf72c305597ed5e7121b80f58528c5c#diff-5ad942ec64a4a90effc70dd2aaea13ca

Configuration via the configure method is likely a possible workaround, but you'd need to encrypt the password as Secret.

This works as expected with Jenkins Core 2.235