message: fix: remove assert module dependency
diff: @@ -28,10 +28,15 @@ import {
  } from 'graphql-language-service-types';
  import { locToRange, offsetToPosition } from 'graphql-language-service-utils';
  -import assert from 'assert';
  export const LANGUAGE = 'GraphQL';
  +function assert(value: any, message: string) {
  + if (!value) {
  + throw new Error(message);
  + }
  +}
  +
  function getRange(text: string, node: ASTNode): Range {
  const location = node.loc as Location;
  assert(location, 'Expected ASTNode to have a location.');
  