Do not keep data from custom date fields when cloning

In issues which have custom fields that are date fields: do not keep data in those fields while cloning.

Workaround

You can clear change closure status field after clone action via a post function.

Steps to do this, you will need Jira Suite Utilities plugin:

1. Edit the workflow.
2. Click on the first step in the workflow.
3. In the "Workflow Browser" section click "Create Issue"/"Create" transition.
4. Add a post function to "Clear Field Value" for each field you don't want to clone.
5. Publish the workflow.

When you do a Clone it will fire the "Create Issue"/"Create" transition on the cloned issue and run the new post functions clearing them out.
Note: The field is also cleared when a new issue is created.