minor, remove unnecessary error message.

le.sh

@@ -398,8 +398,7 @@ _clearupwebbroot() {
     _debug "remove $__webroot/.well-known/acme-challenge/$3"
     rm -rf "$__webroot/.well-known/acme-challenge/$3"
   else
-    _err "removelevel invalid: $2"
-    return 1
+    _info "skip for removelevel:$2"
   fi
   
   return 0