The filter bar's worker version filter does not support worker versions without a revision

Trying to use the worker version or the transcription worker version filters on a project that has a CorpusWorkerVersion on a worker version without a revision causes a TypeError:

Uncaught (in promise) TypeError: can't access property "hash", workerVersion.revision is null
    display filterbar.js:290
    suggestions Bar.vue:142
    inputSuggestions Bar.vue:142