Issue Summary

If multiple milestones are on the same Epic, none will show on the roadmap unless target completion dates are set on at least one objective in each feature.

Steps to Reproduce

Scenario 1:

1. Create an objective A with the type "Roadmap Milestone" and associate it with feature A belonging to epic A. Set a target completion date.
2. Create another objective B with the type "Roadmap Milestone" or "Feature Finisher" and associate it with feature B belonging to the same epic A. Leave the target completion date field blank.
3. Navigate to the roadmap and click on Milestones. Enable objective milestones and click on the show link for all the milestones.

Scenario 2:

1. Create an objective A with the type "Roadmap Milestone" and associate it with feature A belonging to epic A. Set a target completion date.
2. Create another objective B with the type "Roadmap Milestone" or "Feature Finisher" and associate it with feature A and also feature B belonging to the same epic A. Leave the target completion date field blank.
3. Navigate to the roadmap and click on Milestones. Enable objective milestones and click on the show link for all the milestones.

Scenario 3:

1. Create an objective A with the type "Roadmap Milestone" and associate it with feature A belonging to epic A. Set a target completion date.
2. Create another objective B with the type "Roadmap Milestone" or "Feature Finisher" and associate it with feature B belonging to the same epic A. Set a target completion date.
3. Create another objective C with the type "Roadmap Milestone" or "Feature Finisher" and associate it with a feature C belonging to the same epic A. Leave the target completion date field blank.
4. Navigate to the roadmap and click on Milestones. Enable objective milestones and click on the show link for all the milestones.

Expected Results

The roadmap displays milestones with a target completion date set. 

Actual Results

The roadmap does not display any milestones.

Workaround

Set a target completion date for at least one objective associated with each feature belonging to the same epic.