Migrate from lsp-installer to mason

conf/nvim/lua/plugins/lsp.lua

@@ -1,23 +1 @@
 local lspconfig = require('lspconfig')
-
--- lsp installet
---
-local lsp_installer = require("nvim-lsp-installer")
-
--- Register a handler that will be called for each installed server when it's
--- ready (i.e. when installation is finished
--- or if the server is already installed).
-lsp_installer.on_server_ready(function(server)
-    local opts = {}
-
-    -- (optional) Customize the options passed to the server
-    -- if server.name == "tsserver" then
-    --     opts.root_dir = function() ... end
-    -- end
-
-    -- This setup() function will take the provided server configuration and
-    -- decorate it with the necessary properties before passing it onwards to 
-    -- lspconfig Refer to :
-    -- https://github.com/neovim/nvim-lspconfig/blob/master/doc/server_configurations.md
-    server:setup(opts)
-end)