remove separate markdown tools install

the autocommands were screwing up the documentation popups. (it's stil installed as a treesiter plugin though!)

nvim/.config/nvim/lua/plugins/markdown-tools.lua

@@ -1,7 +0,0 @@
-return {
-	"tadmccorkle/markdown.nvim",
-	ft = "markdown", -- or 'event = "VeryLazy"'
-	opts = {
-		-- configuration here or empty for defaults
-	},
-}