Adjust comment

Author: dlarocque

packages/vertexai/test-utils/convert-mocks.ts

@@ -35,8 +35,11 @@ const mockDirs: Record<BackendName, string> = {
 };
 
 /**
- * Generates a file that exports maps from filenames to JSON mock responses (as strings)
+ * Generates a JS file that exports maps from filenames to JSON mock responses (as strings)
  * for each backend.
+ *
+ * This allows tests that run in a browser to access the mock responses without having to 
+ * read from local disk and requiring 'fs'.
  */
 function generateMockLookupFile(): void {
   console.log('Generating mock lookup file...');