[5.x] Prevent infinite loops with Laravel Telescope

[duncanmcclean]

This pull request fixes an issue with Laravel Telescope installed, where an infinite loop would occur if you had entries which link to each other.

Right now, when Telescope encounters an Entry object (whether that be in an event, or in an authorization gate), it'll attempt to serialize it using ->jsonSerialize() which'll return an evaluated array of the augmented entry.

However, if you have an entry which relates back to itself, this evaluated array can cause an infinite loop.

This PR addresses that by returning a shallow augmented array instead, which prevents relationships from being evaluated in the same way, therefore preventing the infinite loop issue.

This fix relies on the formatForTelescope method, added in these Telescope PRs:

• [5.x] Ability to override how objects are serialized laravel/telescope#1562
• Ensure formatForTelescope method is used in request watcher laravel/telescope#1566

Fixes #10782.

[jasonvarga]

I did what was explained in the original issue:

• Added a link field to a collection
• Entry 1 links to Entry 2
• Entry 2 links to Entry 3
• Entry 3 links to Entry 1

The infinite loop still happens when visiting Entry 1 in the CP.

[duncanmcclean]

Good catch! Looks like I missed adding the hook into Telescope's RequestWatcher (which serializes view data) 🙈

I've opened a PR on the Telescope side to address this: laravel/telescope#1566