Suspension public comment is displayed on user profile even if empty

[trichoplax]

Describe the bug
This is very minor. A space appears before the full stop at the end of the standard suspension message shown at the top of a user's profile. This shows as:

This user has been temporarily suspended .

To Reproduce
Steps to reproduce the behavior:

1. Go to a user page as a mod or admin
2. Click on "Moderator Tools"
3. Click on "warn or suspend user"
4. Suspend the user without choosing a public notice
5. See space before full stop as described above

Expected behavior
When there is no public notice to display, there should be no space added.

Additional context
In app/views/users/show.html.erb on line 13:

  <% if @user.community_user.suspension_public_comment.nil? %>

This appears to never evaluate to true, even if no public notice is selected.