xep2md: fix spaces around links or spans

Don't remember why it did this here. There's another spot where it
removes longer stretches of whitespace. Doesn't trim leading or trailing
whitespace tho, but that's what breaks it here.

tools/xep2md.lua

@@ -225,7 +225,7 @@ end
 
 -- Oh god oh god we're all gonna die!
 local function escape_text(event)
-	event.text = event.text:gsub("['&<>\"]", "\\%1"):gsub("^%s+", ""):gsub("%s+$", ""):gsub("%s+", " ");
+	event.text = event.text:gsub("['&<>\"]", "\\%1");
 end
 events.add_handler("#text", escape_text, 1000);