tsconfig.json: enable 'isolatedModules' (#3154)

Author: IvanGoncharov

src/utilities/index.ts

@@ -105,4 +105,4 @@ export {
 export type { BreakingChange, DangerousChange } from './findBreakingChanges';
 
 /** Wrapper type that contains DocumentNode and types that can be deduced from it. */
-export { TypedQueryDocumentNode } from './typedQueryDocumentNode';
+export type { TypedQueryDocumentNode } from './typedQueryDocumentNode';

tsconfig.json

@@ -6,6 +6,7 @@
     "target": "es2019",
     "strict": true,
     "noEmit": true,
+    "isolatedModules": true,
     "forceConsistentCasingInFileNames": true
   }
 }