Kibana version: 7.6.0 BC4

Describe the bug: It used to be that if you had no data in the Elasticsearch cluster, an intermediate page was blocking the app and was linking to Docs and Add Data button. This seems to be gone in BC4.

Steps to reproduce:

1. Start a Cloud instance and don't send any data.
2. Go to the SIEM app.

Looking at the indices, I think this might actually be a change in APM, which seems to pre-create their indices:

 "apm-7.6.0-transaction-000001" : {
    "aliases" : {
      "apm-7.6.0-transaction" : {
        "is_write_index" : true
      }
    }
  }```

Since we match on `apm-*-transaction` by default, that disable the Welcome screen.