Display GPG status of a commit on the commit search page

Problem to solve

The commit search page should display the GPG status as it is done on other pages.

Further details

https://gitlab.com/search?utf8=%E2%9C%93&search=Fix+theme+index+to+match+reality&group_id=&project_id=13083&scope=commits&repository_ref=master:

https://gitlab.com/gitlab-org/gitlab-ce/commits/master?utf8=%E2%9C%93&search=Fix+theme+index+to+match+reality:

Proposal

Use the same layout for the GPG badge as on the commits page.