Enable the lint-raml tool to ignore some specific errors

The "lint-raml" FOLIO CI job (FOLIO-1497) needs to be able to ignore some certain errors.

One such case might be "ERROR JSON schema contains circular references" as encountered in mod-data-import-converter-storage/pull/94.

We did have this once before with RMB-265. Solved with a fix in RMB, and upgrade of the dependencies underlying "lint-raml".

Perhaps this new situation is more convoluted.

Anyway, provide a mechanism in the outer "lint-raml" calling script to detect specific errors issued by the underlying "raml-1-parser" and convert those messages to warnings.