Don't default publishDecorations to true on the server
Don't default publishDecorations to true on the server

If the client doesn't specify this explicitly, that very likely means it doesn't
know about it and so we shouldn't send decorations. In particular, the recent
change to this default caused decorations to be sent to emacs, resulting in a
lot of warning spam.

rust-analyzer/rust-analyzer,rust-analyzer/rust-analyzer,rust-analyzer/rust-analyzer,rust-analyzer/rust-analyzer,rust-analyzer/rust-analyzer