Please prefix the issue title with the project name i.e. [rush], [api-extractor] etc.

Is this a feature or a bug?

• Feature
• Bug

Please describe the actual behavior.

Trying to build docs for Kibana, results in the following error:

(node:8706) UnhandledPromiseRejectionWarning: Error: Internal Error: Cannot assign isExternal=true for the symbol React because it was previously registered with isExternal=false

If the issue is a bug, how can we reproduce it? Please provide detailed steps and include a GitHub branch if applicable. Your issue will get resolved faster if you can make it easy to investigate.

Checkout this KIbana branch https://github.com/lizozom/kibana/tree/newplatform/docs-test
Run yarn kbn bootstrap to install dependencies
Run node scripts/check_core_api_changes.js to start generating the docs.
After ~1min you'll see the error mentioned.

What is the expected behavior?
Docs should be generated

If this is a bug, please provide the tool version, Node.js version, and OS.

• Tool:
• Tool Version:
• Node Version: 10.19.0
  • Is this a LTS version?
  • Have you tested on a LTS version?
• OS: Ubuntu 18.04