Update Generations Workflow to have better error messages

[dmikusa]

Expected Behavior

The update generations workflow runs to have better error messages when it fails.

Current Behavior

If it fails, like here https://github.com/paketo-buildpacks/spring-boot/actions/runs/6844922071/job/18627189425#step:4:7 the error messages are not helpful. Add more information to make it clear why it's failing when it fails.

Motivations

This allows the buildpack to provide guidance to users about the versions of Spring libraries they are using and if they are still supported.

[anthonydahanne]

this issue will be resolved when this one is : spring-io/projects-api#18

we could meanwhile have better error reporting in https://github.com/paketo-buildpacks/pipeline-builder/blob/main/actions/spring-generations/main.go#L47

[anthonydahanne]

this 500 is no longer happening
@dmikusa wanna keep this issue opened for improving the error message?

[dmikusa]

Yes, that sounds good. Moving to pipeline-builder as well.