Project should use bom internally

[snicoll]

The current structure is designed in such a way that the bom is a module like any other modules of this project. This defeats the purpose of testing dependency management internally and separating what is public and what isn't.

The content in its parent (solace-spring-boot-build)has a number of internal/project specific choices that the bom should not know about. The flatten maven plugin is used to publish a "cleaned" bom. That's a great idea but that doesn't shield you from something that may work here and fail in user's project.

A better arrangement would be to move everything build related from -build to -parent and make -parent inherit from the bom. The Spring Initializr project is a concrete example of such arrangement.