Previously, the CLI’s dependency management used proprietary Properties
file-based metadata to configure its dependency management. Since
spring-boot-gradle-plugin’s move to using the separate dependency
management plugin the CLI was the only user of this format.

This commit updates the CLI to use Maven boms to configure its
dependency management. By default it uses the spring-boot-dependencies
bom. This configuration can be augmented and overridden using the new
@DependencyManagementBom annotation which replaces @GrabMetadata.

Closes gh-2688
Closes gh-2439