Move out search for firts ip to the separate script.

get_first_dev_ip.sh

@@ -0,0 +1,11 @@
+#!/bin/bash
+
+for i in $(seq 0 3); do
+    ifname=$(ip -j a|jq -r .[$i].ifname)
+    if [[ "${ifname}" = "lo" ]]; then
+        continue
+    fi
+    echo $(ip -j a|jq -r \
+        ".[$i].addr_info[] | select(.family == \"inet\") | .local")
+    break;
+done