Investigate using @graphql-eslint/eslint-plugin instead of our current plugin

[emmenko]

Investigate using https://github.com/dotansimha/graphql-eslint/ instead of our current plugin.

[mmaltsev-ct]

Background: GraphQL Schema introspection is used to fetch GraphQL Schema (and for instance, populate Docs in GraphiQL UI). The ESLint plugin uses this Schema to validate GraphQL Documents. The plugin we currently use seems to be less maintained and less active than the alternative @graphql-eslint/eslint-plugin.