docs(gatsby-source-graphql): Fix English and clarify fieldName and typeName (#18937)
docs(gatsby-source-graphql): Fix English and clarify fieldName and typeName (#18937)

* Fix English and clarify fieldName and typeName

* chore: format

* Apply suggestions from code review

gatsbyjs/gatsby,gatsbyjs/gatsby,gatsbyjs/gatsby,gatsbyjs/gatsby,gatsbyjs/gatsby,gatsbyjs/gatsby