Karma test is improperly aware of Axios interceptors

In this frequent_items Karma tests, the should render searched projects list test calls vm.$nextTick multiple times in order to work through each interceptor applied to our Axios instance:

.then(vm.$nextTick)
.then(vm.$nextTick)
.then(vm.$nextTick)

I'm not exactly sure why this is necessary (no other tests need these additional calls), but this test fails if the extra calls are removed.

We should rewrite this test to avoid this issue. In its current state, this test will fail whenever a new interceptor is added to Axios.