Given
One running instance of process_version1 waiting at User Task 2

Steps to reproduce
1. Deploy process_version2
2. Start the version migration and change the mapping from User Task 2 to User Task 1
3. Perform the migration.
4. Goto tasklist and select User Task 1.

Actual outcome
Tasklist shows User Task 2 instead of User Task 1

Expected outcome
Tasklist should display User Task 1 because we changed the mapping in the migration