servo: Merge #17115 - Disable macbrew updater (from aneeshusa:temporarily-disable-macbrew-updater); r=emilio

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Source-Repo: https://github.com/servo/servo
Source-Revision: 1aa3eec66bf88f58b547a4ac71c353e774ecc790

--HG--
extra : subtree_source : https%3A//hg.mozilla.org/projects/converted-servo-linear
extra : subtree_revision : c263ab59c07e33f1137b78c836e89f20924d7702

servo/etc/ci/buildbot_steps.yml

@@ -57,7 +57,6 @@ mac-nightly:
   - ./mach build --release
   - ./mach package --release
   - ./mach upload-nightly mac
-  - ./mach upload-nightly macbrew
 
 linux-rel-intermittent:
   - ./mach clean-nightlies --keep 3 --force