clightning: add cli option

An executable is more robust to use than shell aliases.

This is also a preparation for commit 'add module test' because the
NixOS testing framework makes interactive aliases hard to use: It
unsets 'PS1' which is used by programs/bash/bash.nix to detect
interactive shells.

pkgs/nodeinfo/nodeinfo.sh

@@ -5,7 +5,7 @@ BITCOIND_ONION="$(cat /var/lib/onion-chef/operator/bitcoind)"
 echo BITCOIND_ONION="$BITCOIND_ONION"
 
 if [ -x "$(command -v lightning-cli)" ]; then
-    CLIGHTNING_NODEID=$(sudo -u clightning lightning-cli --lightning-dir=/var/lib/clightning getinfo | jq -r '.id')
+    CLIGHTNING_NODEID=$(lightning-cli getinfo | jq -r '.id')
     CLIGHTNING_ONION="$(cat /var/lib/onion-chef/operator/clightning)"
     CLIGHTNING_ID="$CLIGHTNING_NODEID@$CLIGHTNING_ONION:9735"
     echo CLIGHTNING_NODEID="$CLIGHTNING_NODEID"