pinholeIP should only use one IP

Updated piholeIP because if there are multiple network adapters, the gravity list will populate incorrectly with both IP addresses. Only one address should be used.

gravity.sh

@@ -8,7 +8,7 @@ if [[ -f $piholeIPfile ]];then
     rm $piholeIPfile
 else
     # Otherwise, the IP address can be taken directly from the machine, which will happen when the script is run by the user and not the installation script
-    piholeIP=$(ip -4 addr show | awk '{match($0,/[0-9]+\.[0-9]+\.[0-9]+\.[0-9]+/); ip = substr($0,RSTART,RLENGTH); print ip}' | sed '/^\s*$/d' | grep -v "127.0.0.1")
+    piholeIP=$(ip -4 addr show | awk '{match($0,/[0-9]+\.[0-9]+\.[0-9]+\.[0-9]+/); ip = substr($0,RSTART,RLENGTH); print ip}' | sed '/^\s*$/d' | grep -v "127.0.0.1" | (head -n1))
 fi
 
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