Add a "solution" to remove the directive for the diagnostic about invalid metadata directives in documentation comments

[franklinsch]

Feature Name

Provide diagnostic solution for invalid metadata directives in documentation comments

Description

With #1107, we introduced the org.swift.docc.Metadata.Invalid<directive name>InDocumentationComment warning which DocC produces when the Metadata directive has a child directive that isn't supported in documentation comments. It would be nice if DocC would offer a solution to remove that child directive for you.

Motivation

No response

Importance

Not very important, it is easy to remove the problematic directive manually.

Alternatives Considered

No response