feat: merge categories which have matching roots

[lkerford]

What's changed?

In the event we "org.openrewrite.java.test" and "io.moderne.java.test", we want the subcategories "java" and "test" to be merged.
-https://github.com/moderneinc/moderne-recipe-execution/issues/1270

What's your motivation?

We are seeing duplicate entries in the market place and this is confusing.

Any additional context

To achieve the removal of these duplicate categories we decided to merge them in the tree.

The path to a category below a category root today (before any changes) is <categoryRoot>.path.to.sub.category, 
for instance, org.openrewrite.path.to.subcategory. We will instead make that path be path.to.sub.category. 
That means we will merge paths of categories such as io.moderne.java and org.openrewrite.java into java. 
If there are subcategories such as io.moderne.java.spring and org.openrewrite.java.spring, these will
 also be merged into java.spring.

[jkschneider]

Something looks suspicious about this to me. We shouldn't have both packageName and Set of rootPackages. Which of the set of rootPackages does packageName represent?

[lkerford]

packageName does not include the root so that we can merge the packages together
while the rootPackages contains all the know subset of roots.

For example org.openrewrite.path.to.subcategory has a packageName of path.to.subcategory and a rootPackages of listof(org.openrewrite)

[pstreef]

I guess we should rename packageName then, to avoid this confusion.