Make linux OS detection more generic

Author: keyboardsage

install.sh

@@ -40,7 +40,7 @@ fi
 curl -sS https://raw.githubusercontent.com/0xacx/chatGPT-shell-cli/main/chatgpt.sh -o /usr/local/bin/chatgpt
 
 # Replace open image command with xdg-open for linux systems
-if [[ "$OSTYPE" == "linux-gnu"* ]] || [[ "$OSTYPE" == "freebsd"* ]]; then
+if [[ "$OSTYPE" == "linux"* ]] || [[ "$OSTYPE" == "freebsd"* ]]; then
   sed -i 's/open "\${image_url}"/xdg-open "\${image_url}"/g' '/usr/local/bin/chatgpt'
 fi
 chmod +x /usr/local/bin/chatgpt