Allow to import time entries for issues in different projects
As it is now, the time entry import only allows to import time entries for a single, pre-selected project. Because time entries can only be imported for already existing issues (which in turn already belong to a project), by definition that pre-selected project is only relevant for time entries that are not attached to any issue.
The attached patch that was extracted from Planio allows to import time entries for issues across different projects. This is achieved simply by ignoring the user-selected project for those rows where an issue id is present, letting the existing logic in
TimeLogEntry#safe_attributes= determine the project id.
This is somewhat related to #25808.