Progress bars are not properly placed in milestones list

They're not properly centered with the row.

Central issue gitlab-foss#18867 (closed)

mentioned in issue gitlab-foss#18867 (closed)

Do you still feel the same with the current version @cperessini? If so, can you give an example of what it should look like so that we can put it as up-for-grabs ?

changed milestone to %9.5 in gitlab-foss

moved from gitlab-foss#18965 (moved)

mentioned in commit 8b5c7e98