linkchecker: Treat directory links as errors
linkchecker: Treat directory links as errors

Directory links don't work well offline so they should be treated as errors.

graydon/rust,graydon/rust,aidancully/rust,graydon/rust,GBGamer/rust,aidancully/rust,graydon/rust,aidancully/rust,graydon/rust,GBGamer/rust,GBGamer/rust,GBGamer/rust,GBGamer/rust,graydon/rust,aidancully/rust,aidancully/rust,aidancully/rust,GBGamer/rust,GBGamer/rust,GBGamer/rust