You can remove a progress tracker from a project.

Steps

If you want to remove a Progress Tracker from several projects at once, take this approach instead.

Select Home in the top menu
Scroll down to the Projects box
Press the cog icon next to the project you want to remove a progress tracker from
A dropdown menu appears
Select Targets
You arrive on the project’s targets page which displays the progress trackers being used on the project
Press Remove Tracker next to the progress tracker you want to remove from the project
This causes it to disappear. Now press Save
You arrive on the project page. That’s it

Makerble User Guide