Suggested additions to migration guide to make the process easier for users

[cramatt]

Is your feature request related to a problem? Please describe.

While upgrading from 1x to 3x It was not clear based on the guide that I MUST upgrade to ApolloServer 3, since graphql 16+ requires this. Additionally, I needed to go find the graphql changelog which I think just including for users in the guide would be easier.

I also suspect more users than you think will need to upgrade from 1x to 3x since the GRANDSTACK starter still installs 1x as you can see in their lock file.

Describe the solution you'd like

1. Add a mention at end of migration guide that ApolloServer 3.0 is required, maybe after this section.
2. Add a link to the graphql 16 changelog which included breaking changes and is something most upgraders will need to dig up manually.

Describe alternatives you've considered None

Additional context None

[cramatt]

To further clarify, Apollo Server 3.5.x is required. Here is their migration guide: https://www.apollographql.com/docs/apollo-server/migration/

And here is the issue tracking that GraphQL 16 supports is added to 3.5.x and later. https://github.com/apollographql/apollo-server/issues/5605#issuecomment-967437447