meta information not matching between main.nf and meta.yml should result in failure

[mahesh-panchal]

Description of feature

At the moment, when the meta.yml doesn't match the main.nf, linting issues are listed as warnings. If inputs and outputs are not described in the meta, this should result in a linting failure, rather than a warning.
Currently, warnings don't trigger any messages on PR's and so input changes can often go unspecified by the meta.yml.

[mirpedrol]

done