Document GHC ABI issues here as well

[hasufell]

https://github.com/haskell/vscode-haskell#ghc-abis-dont-match doesn't just apply to vscode, but any other LSP client configuration. There were reports of nvim user hitting this, so we should document it somewhere in the HLS docs as well.

[mortezadadgar]

I'm very new to haskell and i don't get why hls must be compiled with same compiler of ghcup; I have compiled the ghc-9.0.2 on my gentoo which is certainly a version that is supported
I have to either uses ghcup for ghc, hls and cabal installation and ditches the package manger out of window or relay on compiling hls from source which costs me around ~240 to be installed