Replaced the trac specific ticket link with a general link.

Bug description: when you use the pushmanager create bookmarklet on a review
boad CR, jira tickets are not parsed correctly. They are thought to be trac
tickets, and an incorrect trac link is generated in the PR comments.

Ref: (PUSHMGR-63) Pushmanager Create does not parse jira issues correctly
This string is formatted with a javascript function, not python. Do you have any better idea for the %TICKET% part?