Copy comment link to clipboard

Description / Proposal

• We link to comments a lot. This would extend our copying / clipboard mechanism to a linked comment.
• Place the clipboard icon as in the screenshot, in each comment within any comment thread in GitLab.

* When you hover on the clipboard, it says "Copy URL to clipboard", similar to what you get on the project page: * When you click on the icon, you copy the link to the comment to the clipboard.

Single source of truth

Copy link icon is place to the right of the timestamp and is always visual on all screen sizes.