Image building requires builder to specify a stack

[bpfoster]

According to the buildpacks documentation, stacks were deprecated in Platform API 0.12 and Buildpack API 0.10 (https://buildpacks.io/docs/for-app-developers/concepts/base-images/stack/).

If I try to use a custom builder that does not define a stack, the spring boot maven plugin gives an error:

Execution default of goal org.springframework.boot:spring-boot-maven-plugin:3.3.0:build-image-no-fork failed: Run image must be specified in the builder image stack

The builder defines the images as per the documentation, like

[build]
image = "cnbs/sample-base-build:jammy"
[run]
[[run.images]]
image = "cnbs/sample-base-run:jammy"

If I try and work around this by specifying the runImage in the spring-boot-maven-plugin configuration, I get another error

Execution default of goal org.springframework.boot:spring-boot-maven-plugin:3.3.0:build-image-no-fork failed: Missing 'io.buildpacks.stack.id' stack label

It would be good to support builders that follow the new method and which do not use stacks.