Merge branch 'add-project-scope-to-live-trace-feature-flag' into 'master'

Add project scope to live trace feature flag

See merge request gitlab-org/gitlab-ce!31325

(cherry picked from commit bea3d730)

759a3484 Add project scope to live trace feature flag

lib/gitlab/ci/trace.rb

@@ -126,7 +126,7 @@ module Gitlab
             raise AlreadyArchivedError, 'Could not write to the archived trace'
           elsif current_path
             File.open(current_path, mode)
-          elsif Feature.enabled?('ci_enable_live_trace')
+          elsif Feature.enabled?('ci_enable_live_trace', job.project)
             Gitlab::Ci::Trace::ChunkedIO.new(job)
           else
             File.open(ensure_path, mode)