Jira Cloud to Cloud C2C should warn about data that is not migrated

Issue Summary

In What migrates in a cloud-to-cloud migration for Jira, a number of entities are listed as not compatible with migration.

There should be an explicit warning about what data may not be migrated.

Sample list

• Custom field language translations
• Workflow functions
  • Condition: subtask blocking
  • Post function: clear field value, copy value from other field, delegating, update issue custom field
• Notification schemes (projects are added to the default schemes in cloud)
• Project avatars
• Links to issues or entities not migrated
• Automation rules (including project-level automation rules)
• Custom issue type icons
• Mail handlers
• Single version custom field
• Select list (cascading)
• Project picker

Expected Results

There is a GUI warning about entities that may not be migrated.

Actual Results

Migration proceeds without warning. In some cases, a message is logged in the post-migration logs:

UNSUPPORTED,ABC,Issue,ABC-64,Custom field value,The "Release Version" custom field is not supported via migration. The value for the change group in this issue will not be migrated.,If you require this custom field, re-create it in your cloud site and use a csv import to update the issues post migration. Learn more : https://support.atlassian.com/jira-cloud-administration/docs/import-data-from-a-csv-file/