TypeError: enum_exists(): Argument #1 ($enum) must be of type string, null given, called in /.../ResolveForPropertyValueAction.php on line 37

[stevebauman]

Describe the bug
After updating to v4.7.0, I now receive the below exception in several areas of my application:

TypeError: enum_exists(): Argument #1 ($enum) must be of type string, null given, called in /.../ResolveForPropertyValueAction.php on line 37

To Reproduce
Create a new activity log with a null value for a custom property.

Expected behavior

This is a new exception. I'm assuming this is due to a custom property being set to null in my application:

laravel-activitylog/src/ActivityLogger.php

Line 106 in 89aee26

$this->getActivity()->properties = collect($properties)->map(fn ($value) => ResolveForPropertyValueAction::execute($value));

Versions (please complete the following information)

• PHP: 8.0
• Database: MySQL 8.0
• Laravel: 9.39
• Package: 4.7.0

Stack Trace

TypeError: enum_exists(): Argument #1 ($enum) must be of type string, null given, called in .../vendor/spatie/laravel-activitylog/src/Actions/ResolveForPropertyValueAction.php on line 37
.../vendor/symfony/polyfill-php81/bootstrap.php:27
.../vendor/spatie/laravel-activitylog/src/Actions/ResolveForPropertyValueAction.php:37
.../vendor/spatie/laravel-activitylog/src/Actions/ResolveForPropertyValueAction.php:22
.../vendor/spatie/laravel-activitylog/src/ActivityLogger.php:106
.../vendor/laravel/framework/src/Illuminate/Collections/Arr.php:560
.../vendor/laravel/framework/src/Illuminate/Collections/Collection.php:719
.../vendor/spatie/laravel-activitylog/src/ActivityLogger.php:106