More rm fixes

root/usr/libexec/apps/btcpayserver/btcpayserver.sh

@@ -84,7 +84,10 @@ case "${ACTION}" in
       docker stop "$ID"
       docker rm "$ID"
     done
-    docker rmi -f $(docker images | grep 'btcpayserver' | awk '{print $3}')
+    IMAGE_IDS=$(docker images | grep 'btcpayserver' | awk '{print $3}')
+    if [ -n "$IMAGE_IDS" ]; then
+        docker rmi -f $IMAGE_IDS
+    fi
     rm -r /opt/docker2/compose/btcpayserver  2>/dev/null
     rm -rf /opt/docker2/compose/btcpayserver/btcpayserver-docker 2>/dev/null  # Removing the btcpayserver-docker directory
     ;;