fix(ruby_lsp): set cmd_cwd to root_dir

[RichGuk]

Problem:

When running from a directory other than root (i.e monorepo), ruby-lsp does not load correctly. Unsure why, previous lspconfig had cmd_cwd set to the same as root_dir.

Solution:

Set the cmd_cwd via reuse_client(), similar to ast_grep. See #3850, #4082 for more details.

Tested both from root_dir and monorepo multi-root.

[RichGuk]

Previous lspconfig:

nvim-lspconfig/lua/lspconfig/manager.lua

Lines 116 to 120 in 33d351c

	-- Launch the server in the root directory used internally by lspconfig, if otherwise unset
	-- also check that the path exist
	if not new_config.cmd_cwd and vim.uv.fs_realpath(root_dir) then
	new_config.cmd_cwd = root_dir
	end

[justinmk]

Previous lspconfig:

Oh interesting. I wonder if vim.lsp.config should do that by default @lewis6991 ?

[lewis6991]

Previous lspconfig:

Oh interesting. I wonder if vim.lsp.config should do that by default @lewis6991 ?

Yeah, maybe.