PR Checklist

Please check if your PR fulfills the following requirements:

• The commit message follows our guidelines: https://github.com/nestjs/nest/blob/master/CONTRIBUTING.md
• Tests for the changes have been added (for bug fixes / features)
• Docs have been added / updated (for bug fixes / features)

If you think this is an acceptable change, I'll work on documenting it and adding the tests.

PR Type

What kind of change does this PR introduce?

• Bugfix
• Feature
• Code style update (formatting, local variables)
• Refactoring (no functional changes, no api changes)
• Build related changes
• CI related changes
• Other... Please describe:

What is the current behavior?

Orphaned GraphQL types are automatically added to the schema.

What is the new behavior?

If the new BuildSchemaOption option is explicitly set to false, automatically detected orphans won't get added to the schema.

Does this PR introduce a breaking change?

• Yes
• No

Other information

The behaviour of automatically registering all declared GraphQL is undesirable for our use case.