Add dot to separate system note contents from timestamp
Description
Originally from https://gitlab.com/gitlab-org/gitlab-ee/issues/1481#note_69555346
https://gitlab.com/gitlab-org/gitlab-ce/issues/40402 added a comma ,
to time tracking system notes, so that the values are separated from the timestamp. Ex: @victorwu changed time estimate to 1h 30min, 30 minutes ago
However, the comma solution doesn't apply nicely to the weight system notes. The comma works for time tracking because you have the time unit (h, min) whereas in weights there are no units, just a number.
Proposal
Add a dot character and apply a lighter text color (#919191
) to the timestamp, making a clear separation between the contents and the timestamp.
This design should be applied to all system notes, including comments, in issues, merge requests, and epics.
Any commas introduced previously should be removed.
Example: