feat: add PyrightSetPythonPath command to pyright config

[ianliu]

The new command accepts a single path for a python executable that will be used to reconfigure the pyright language server. This is useful to change which python will be used by pyright without having to activate the python environment beforehand. The act of finding which python executable to use isn't handled here.

[github-actions]

Do not change server_configurations.md directly. Edit the lua source file instead. See https://github.com/neovim/nvim-lspconfig/blob/master/CONTRIBUTING.md#generating-docs

[glepnir]

please don't edit the doc. it auto generate from lua file.

[ianliu]

@glepnir I did a force push to revert doc changes

[justinmk]

See discussion in #1937

I'm thinking we might want some sort of "sub-command" entrypoint so that langserver-specific commands can be discovered. E.g. :Lsp <tab> would complete all available commands provided. And :LspCapabilties <tab> would show... something.

[ianliu]

@justinmk maybe this could be done in this function:

nvim-lspconfig/lua/lspconfig/util.lua

Lines 88 to 95 in c6105c4

	function M.create_module_commands(module_name, commands)
	for command_name, def in pairs(commands) do
	local opts = M._parse_user_command_options(def)
	api.nvim_create_user_command(command_name, function(info)
	require('lspconfig')[module_name].commands[command_name][1](unpack(info.fargs))
	end, opts)
	end
	end

and keep the declarative definitions of commands intact.