Not support for activerecord 6

[kalfaron]

Bundler could not find compatible versions for gem "activerecord":
In snapshot (Gemfile.lock):
activerecord (= 6.0.2.1)

In Gemfile:
graphql-preload was resolved to 1.0.1, which depends on
activerecord (<= 5, >= 3.2)

rails (= 6.0.2.1) was resolved to 6.0.2.1, which depends on
  activerecord (= 6.0.2.1)

[Envek]

@kalfaron , you can use my fork (we're using it in one of our projects with Rails 6 and GraphQL-Ruby 1.11):

gem "graphql-preload", git: "https://github.com/Envek/graphql-preload"