Stop publishing redirect artifacts at `com.diffplug.gradle.spotless`

https://plugins.gradle.org/plugin/com.diffplug.gradle.spotless

It has

```
Add this plugin to your build using the [plugins DSL](https://docs.gradle.org/current/userguide/plugins.html#sec:plugins_block):

plugins {
id("com.diffplug.gradle.spotless") version "8.2.1"
}
```

if you do that you get:

```
Caused by: org.gradle.api.GradleException: We have moved from 'com.diffplug.gradle.spotless'
to 'com.diffplug.spotless'
To migrate:
- Test your build with: id 'com.diffplug.gradle.spotless' version '4.5.1'
- Fix any deprecation warnings (shouldn't be many / any)
- Now you can use: id 'com.diffplug.spotless' version '5.0.0'
```