chore: standardize that doc comments on top of statements and expression are allowed but warn#7450

TomAFrench merged 2 commits intomasternoir-lang/noir:masterfrom

ab/disallow-doc-comments-on-top-of-let-and-unsafenoir-lang/noir:ab/disallow-doc-comments-on-top-of-let-and-unsafeCopy head branch name to clipboard