Use independant Taskcluster route

[La0]

We are still using the TC routes & scopes from mozilla/release-services:

• index:insert-task:project.releng.services.project.testing.static_analysis_bot.*
• index:insert-task:project.releng.services.tasks.*

A simple rename to a relman prefix + code-review should be OK.

The frontend will need to support both current & new prefixes for a while.

[La0]

Both old & new routes are published on testing now https://tools.taskcluster.net/index/project.relman.testing.code-review.phabricator

I just deployed current master on testing, and added some scopes in the hook's roles (also did that for production).

We just need to make a new release to enable that in production.