In case you don't see it. the cart behind the magnifying glass, it says "Torchwood" (i had to search for it pretty long)
I think it's just an Easter egg in the show. Steven Moffat has said multiple times that in the Doctor Who universe, Sherlock holmes is just a story, like in ours.
Maybe Sherlock is a Torchwood fan and it's some kind of merch?
Sherlock Holmes already exists as an actual Victorian person and a fictional character at the same time in the Whoniverse. Even if an organization called Torchwood exists, doesn't mean all of Doctor Who exists with it.