stripe apps create fails inside monorepo with non-SPDX license in root package.json

[tvanantwerp]

Describe the bug
When using a monorepo with a root-level package.json with a non-SPDX license (e.g., the ~~proprietary~~ license specified in a generated Stripe App package.json), the Stripe App creation script fails with the following error:

🖊️ Enter details of your new Stripe app (these can be changed later)
App ID: com.example.stripe-app
Display name: Stripe App
✔ Created skeleton files
✔ Created default view
✔ Wrote package.json
yarn add v1.22.19
warning ../../package.json: License should be a valid SPDX license expression
info No lockfile found.
warning [email protected]: License should be a valid SPDX license expression
info Visit https://yarnpkg.com/en/docs/cli/add for documentation about this command.
error Workspaces can only be enabled in private projects.
exit status 1

This failure results in an unfinished Stripe App setup. It does generate a package.json and several supporting files, but it is incomplete. I've only noticed problems with the package.json file, such as these below:

  "dependencies": null,
  "engines": {
    "node": "\u003e=14"
  },

No yarn.lock file is generated on error.

I've been able to replicate this error for both pnpm workspaces and yarn workspaces.

To Reproduce
Steps to reproduce the behavior:

1. Create a monorepo directory, e.g., mkdir my-stripe-app-monorepo
2. Initialize a new Node project by creating a package.json
3. Change the license to a non-SPDX license, e.g. ~~proprietary~~
4. Set up workspaces
   • Create a packages directory
   • For yarn: add the following to package.json

     "workspaces": [
       "packages/*"
     ]
     

   • For pnpm: create pnpm-workspaces.yml and add the following:

     packages:
         - 'packages/*'
     

5. cd packages and run stripe apps create my_stripe_app

Expected behavior
Creation of a new Stripe App as a monorepo package should not fail if it doesn't recognize the root-level package.json's license field as an SPDX license.

Desktop (please complete the following information):

• OS: macOS 13.4.1
• yarn: 1.22.19
• pnpm: 8.6.6
• Stripe CLI: 1.15.0
• Stripe Apps CLI: 1.5.10