Merge request widget issue reference should have (closed)

Resources

FE @jschatz1

• In the screenshot below, the Closes issue #26481 near the bottom should have (closed) next to it, similar to what it is above higher in the screenshot.

• Also, it should simply say Closes #26481 (closed). <- This will be changed in https://gitlab.com/gitlab-org/gitlab-ce/issues/32641.

Original issue

• Original title

Warning if MR auto closes an issue that is already closed

• Original description

If an issue has been closed, any MR which attempts to 'auto close' the issue should show a warning or be blocked, as the commit message needs to be updated, and possibly the MR needs to be re-evaluated