[FEATURE] allow reducing blocking validation errors to warnings

[JoernBerkefeld]

sometimes edge cases simply require skipping otherwise good rules. For these scenarios, we need a flag for:

• buildDefinition
• buildDefinitionBulk
• build
• deploy

...that allows to reduce the severity of a validation's outcome from a blocking error to a non-blocking warning.
Imagine you are prepping a deployment with --matchName and need to fix folders before having it override but cannot change the key for one reason or another.

[github-actions]

Closed by #1672.