Enable sortpom on the bom module

[korthout]

It seems the sortpom-plugin is not enabled on the bom/pom.xml. Let's enable it

Originally posted by @korthout in #8032 (comment)

[npepinpe]

Do you remember why we don't use the spotless built-in sortPom?

https://github.com/diffplug/spotless/blob/main/plugin-maven/README.md#sortpom

[npepinpe]

Anyway, the biggest blocker here is that profile inheritance is sketchy in Maven. You don't actually inherit profiles, but they can be activated for child modules. What this means is, if you have a profile autoFormat defined in zeebe-bom, you can activate it and it will be enabled for zeebe-parent. However, you cannot extend it or modify it in zeebe-parent.

In our case, this means we would need to move the licensing configuration into the bom as well, not just spotless. This could be a good push for us to consider using spotless for licensing first, that way all we need is, well, spotless.

[korthout]

Do you remember why we don't use the spotless built-in sortPom?

Historical. No time spend on it when we switched to spotless.