feat: Add option to sort schema using lexicographicSortSchema

[clord]

This can be helpful for avoiding merge issues, for example.

[clord]

@maticzav not sure who to ping. I'm using get-graphql-schema for a project but the schema is always changing order on the backend, causing merge conflicts. we need to commit since there is no single source of truth for schema, it depends on which feature is being worked on. this new option would sort using built-in lexicographic schema sorting.

[beaugunderson]

Also interested in this, I tried jq --sort-keys and json-sort-cli and neither provided a stable ordering.

I'll note that even the non-JSON output changes order sometimes.