report errors for use of lspconfig.lspname in Nvim 0.11+

[idbrii]

Description

I updated lspconfig and had to bisect to figure out why my lsp configuration didn't work anymore. :checkhealth lsp shows my configuration, but they're only applied to one instance of each lsp server (one lua-ls has settings and the others have an empty table).

I couldn't find news or changelog, but I was also very out of date. I updated from something pre-v2.0.0 and bisected my issue to this change:
#3659

Could we update checkhealth to warn nvim v0.11+ users that they're using the wrong method to setup their lsp?

[justinmk]

The plan is to actually throw an error if Nvim 0.11+ invokes anything in lua/lspconfig/ (as opposed to lsp/) . It's probably time to make that change now.

I couldn't find news or changelog, but I was also very out of date. I updated from something pre-v2.0.0 and bisected my issue to this change: #3659

In theory, a major version bump is a strong signal that there were breaking changes :) And we have pinned this issue: #3693