Bug 1377770 - Mac OS X Cross compiled nightly builds should be tier 1 r=Callek

MozReview-Commit-ID: ZohVcuU6gl

--HG--
extra : rebase_source : 3e7ad694487440e38085bf44dc3443fde8863e49

taskcluster/ci/build/macosx.yml

@@ -131,7 +131,7 @@ macosx64-nightly/opt:
     treeherder:
         platform: osx-cross/opt
         symbol: tc(N)
-        tier: 2
+        tier: 1
     worker-type: aws-provisioner-v1/gecko-{level}-b-macosx64
     worker:
         max-run-time: 36000