Consider OpenAPI extension `x-no-relation` also in other pertinent place

[SOHELAHMED7]

PR #21 introduced new OpenAPI extension x-no-relation.

Currently it is only considered in faker generation.

It should also be considered in other pertinent code generation such as model, migrations etc.

This should be done after above PR is merged.

[SOHELAHMED7]

Do this once #21 is merged.