Add reference_browser and fenix repositories

[davehunt]

We now have results based on the reference-browser and fenix repositories:

• https://treeherder.mozilla.org/#/jobs?repo=reference-browser
• https://treeherder.mozilla.org/#/jobs?repo=fenix

It would be useful to be able to query this data.

[klahnakoski]

https://activedata.allizom.org/tools/query.html#query_id=ZZG6phkT

[davehunt]

An example of a passing Raptor job for Fenix can be found here: https://treeherder.mozilla.org/#/jobs?repo=fenix&revision=449fffe9330101428ffa1fb4234c83b13f2e2faf&selectedJob=244073160

[davehunt]

An example of a passing Raptor job for Reference Browser can be found here: https://treeherder.mozilla.org/#/jobs?repo=reference-browser&revision=df9337bc68b70c34dfce6f09c453f3e934b77689&selectedJob=244407354