API builds improvements: ability to filter builds by stages
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For now it is possible to filter builds in project GET /projects/:id/builds
only by **scope**
> The scope of builds to show, one or array of: pending, running, failed, success, canceled; showing all builds if none provided
It will be good to filter also by stage.
As an example - often you want to get last successful/failed build for a particular stage.
Like give me last success run for unit-tests stage for project MyProject.
issue