generateJava fails while .graphqlconfig is present in the schema dir

It seems the plugin simply concatenates all files inside the schema dir(s) and then tries to parse them. Why would it do so? Why does it include the .graphqlconfig file as well? There doesn't seem to be any option to exclude some files from the schema paths, unfortunatelly.

Execution failed for task ':app:generateJava'.
> Unable to parse the schema...
  Invalid Syntax : offending token '"schemaPath"' at line 2 column 3

Then it prints the whole schema and apparently the contents of .graphqlconfig is part of it:

  {
    "schemaPath": "schema.graphql"
  }

Start at the schema-directory handling used by the generateJava task and reproduce the failure with a .graphqlconfig file beside the schema. Trace how files are selected and parsed; done means generation no longer attempts to parse .graphqlconfig files, with coverage for this directory layout.