Callout for errors like: TypeError: Cannot read properties of null (reading 'id')

**Describe the content issue**:
A clear and concise description of what the content issue is. Is there content missing or is there incorrect content?

There should be a callout for errors where subscription and mutation selection sets don't match, resulting in errors like the following:

`TypeError: Cannot read properties of null (reading 'id')`

Add to the Troubleshooting section for discoverability

**URL page where content issue is**: