GlBreadcrumb compat jest errors

What

When mounting GlBreadcrumb on jest the following error occurs.

Test suite failed to run

    Jest worker encountered 4 child process exceptions, exceeding retry limit

      at ChildProcessWorker.initialize (node_modules/jest-worker/build/workers/ChildProcessWorker.js:181:21)

/Users/marinamosti/Developer/switchboard/node_modules/@gitlab/ui/dist/components/base/breadcrumb/breadcrumb.js:152
              _this.$refs.breadcrumbs.forEach(function (b, index) {
                                      ^

TypeError: _this.$refs.breadcrumbs.forEach is not a function
    at _callee$ (/Users/marinamosti/Developer/switchboard/node_modules/@gitlab/ui/dist/components/base/breadcrumb/breadcrumb.js:152:39)
    at tryCatch (/Users/marinamosti/Developer/switchboard/node_modules/@gitlab/ui/dist/components/base/breadcrumb/breadcrumb.js:17:1062)
    at Generator.<anonymous> (/Users/marinamosti/Developer/switchboard/node_modules/@gitlab/ui/dist/components/base/breadcrumb/breadcrumb.js:17:3012)
    at Generator.next (/Users/marinamosti/Developer/switchboard/node_modules/@gitlab/ui/dist/components/base/breadcrumb/breadcrumb.js:17:1699)
    at asyncGeneratorStep (/Users/marinamosti/Developer/switchboard/node_modules/@gitlab/ui/dist/components/base/breadcrumb/breadcrumb.js:18:103)
    at _next (/Users/marinamosti/Developer/switchboard/node_modules/@gitlab/ui/dist/components/base/breadcrumb/breadcrumb.js:19:194)
    at processTicksAndRejections (node:internal/process/task_queues:95:5)

Why this is happening as at this moment unclear, I would take a wild guess that it has something to do with the changes to v-for and array template refs.

Possibly related to b58ba764

The update to gitlab UI came at the same time as the MR that implemented GlBreadcrumb on switchboard so its unclear which is the culprit.