add dangling_library_doc_comments, remove prefer_void_to_null

[devoncarew]

• add dangling_library_doc_comments to core (#148)
• remove prefer_void_to_null from recommended (#154)

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Package publishing

Package	Version	Status	Publish tag (post-merge)
package:lints	3.0.0-beta.2	ready to publish	v3.0.0-beta.2

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