nixos/drupal: only append nixos settings if it hasn't been done yet (#507078)

          cp "$default_settings_file" "$settings_file"

        fi

        if ! grep -qF "require dirname(__FILE__) . '/settings.nixos-${hostName}.php';" ${cfg.stateDir}/sites/default/settings.php; then

          echo "Appending NixOS generated settings..."

          cat < ${appendSettings hostName} >> "$settings_file"

        chmod 644 "$settings_file"

        fi

        # Link the NixOS-managed settings file to the state directory.

        ln -sf ${drupalSettings hostName cfg} ${cfg.stateDir}/sites/default/settings.nixos-${hostName}.php