Filed by: nerli [at] mozilla.com
Parsed log: https://treeherder.mozilla.org/logviewer?job_id=351943633&repo=autoland
Full log: https://firefox-ci-tc.services.mozilla.com/api/queue/v1/task/RQ-15zYfTP-evGtmWe8kvg/runs/0/artifacts/public/logs/live_backing.log

[task 2021-09-17T22:05:57.636Z] Error running mach:
[task 2021-09-17T22:05:57.636Z] 
[task 2021-09-17T22:05:57.636Z]     ['wpt-manifest-update', '--config', 'testing/web-platform/wptrunner.ini', '--no-download']
[task 2021-09-17T22:05:57.636Z] 
[task 2021-09-17T22:05:57.636Z] The error occurred in the implementation of the invoked mach command.
[task 2021-09-17T22:05:57.636Z] 
[task 2021-09-17T22:05:57.636Z] This should never occur and is likely a bug in the implementation of that
[task 2021-09-17T22:05:57.636Z] command.
[task 2021-09-17T22:05:57.636Z] You can invoke |./mach busted| to check if this issue is already on file. If it
[task 2021-09-17T22:05:57.636Z] isn't, please use |./mach busted file wpt-manifest-update| to report it. If |./mach busted| is
[task 2021-09-17T22:05:57.636Z] misbehaving, you can also inspect the dependencies of bug 1543241.
[task 2021-09-17T22:05:57.637Z] 
[task 2021-09-17T22:05:57.637Z] If filing a bug, please include the full output of mach, including this error
[task 2021-09-17T22:05:57.637Z] message.
[task 2021-09-17T22:05:57.637Z] 
[task 2021-09-17T22:05:57.637Z] The details of the failure are as follows:
[task 2021-09-17T22:05:57.637Z] 
[task 2021-09-17T22:05:57.637Z] TypeError: 'staticmethod' object is not callable
[task 2021-09-17T22:05:57.637Z] 
[task 2021-09-17T22:05:57.637Z]   File "/builds/worker/checkouts/gecko/testing/web-platform/mach_commands.py", line 564, in wpt_manifest_update
[task 2021-09-17T22:05:57.637Z]     setup(command_context)
[taskcluster 2021-09-17 22:05:58.259Z] === Task Finished ===
[taskcluster 2021-09-17 22:05:58.380Z] Artifact "public/manifests.tar.gz" not found at "/builds/worker/checkouts/gecko/manifests.tar.gz"
[taskcluster 2021-09-17 22:05:58.479Z] Unsuccessful task run with exit code: 1 completed in 10.655 seconds

Ah, the setup() function needs to have its @staticmethod decorator removed.

Closing this since the initial bug that caused this, was backed out: https://hg.mozilla.org/integration/autoland/rev/e28c911d36db5524416becf1781c231a058e6c21