Comments on attributes do not merge correctly

[djalters2]

Describe the bug
In the case of "Handling Relations Across Files" (see prisma-aurora README), adding comments to attributes are not merged correctly on the aurora-built prisma schema

NB In our use case we using 3 slashes for comments /// as this is required for a different prisma library we are using that generates documentation and displays comments from the schema as descriptions. The error also occurs with 2 slashes //

To Reproduce
Steps to reproduce the behavior:

1. Create 2 models with relationships in different files, i.e. Author and Book per prisma-aurora README
2. Create a prisma-aurora json config file
3. Add a comment above the attributes on the models, e.g. /// my comment
4. View the built prisma schema

Expected behavior
The prisma schema should be built with attribute comments deduped/merged appropriately

Screenshots

Desktop (please complete the following information):

• Ubuntu
• 20.04.4

Additional context

• Node fermium