Fix broken link in docs

[runjak]

Hi :slightly_smiling_face: :wave:,

when browsing node-postgres.com/features/queries I noticed that the link to the types API a the bottom of the page appears to be broken. It seemed likely that the intention was to link to node-postgres.com/apis/types instead.

Similarly since api related documentation pages are hosted under /apis/ instead of /api/ I'd suggest adjusting the slugs in some cases.