Enhancing Validate script to identify location of the errors

[Preeticp]

The Validate script is awesome for finding out errors. It could be even more useful, if it could identify the modules in which the errors are seen, reducing the time spent in searching for the error, especially when you tackle multiple modules in a PR.
For example: Processing e2e_workshop failed to build

asciidoctor: WARNING: invalid reference: reducing_project_memory_usage
asciidoctor: WARNING: invalid reference: reducing_project_memory_usage

Links used here were missing the context for the module being reused, but that was not obvious, nor was the location for these errors.

It would be great if we have a message like how we have for merge conflicts: CONFLICT (content): Merge conflict in docs/topics/modules/reviewing_resource_information_cli.adoc

Interim solution:
Run the following from the root of the repo:
grep -r reducing_project_memory_usage

[rkratky]

Error/warning messages reference: https://github.com/asciidoctor/asciidoctor.org/blob/master/docs/_includes/messages.adoc