fix: allow port number in callback URLs of API_ONLY apps

[bflorian]

Checklist

• [x] I have read the CONTRIBUTING document
• [ ] Any required documentation has been added
• [x] My code follows the code style of this project (npm run lint produces no warnings/errors)
• [x] I have added tests to cover my changes

[changeset-bot[bot]]

🦋 Changeset detected

Latest commit: 84de99e5e3550bc1d08748b56857f5145f8cbe83

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

| Name | Type | | -------------------- | ----- | | @smartthings/cli-lib | Patch |

Not sure what this means? Click here to learn what changesets are.

Click here if you're a maintainer who wants to add another changeset to this PR