Fix missing db_pwd

scripts/upgrade

@@ -22,7 +22,7 @@ is_public=$(ynh_app_setting_get --app=$app --key=is_public)
 final_path=$(ynh_app_setting_get --app=$app --key=final_path)
 db_name=$(ynh_app_setting_get --app=$app --key=db_name)
 db_user=$db_name
-db_pwd=$(ynh_app_setting_get --app=$app --key=db_pwd)
+db_pwd=$(ynh_app_setting_get --app=$app --key=mysqlpwd)
 phpversion=$(ynh_app_setting_get --app=$app --key=phpversion)
 
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