fix: Add 'None' option to payment method dropdown to allow resetting payment config

Fixes #583

- Added PAYMENT_METHOD_NONE as the first option in the payment method dropdown
- Removed placeholderMessage since 'None' is now a selectable option
- Users can now reset their payment configuration by selecting 'None'

Author: clbotdev

apps/web/components/admin/settings/index.tsx

@@ -813,6 +813,10 @@ const Settings = (props: SettingsProps) => {
                                 newSettings.paymentMethod || PAYMENT_METHOD_NONE
                             }
                             options={[
+                                {
+                                    label: SITE_SETTINGS_PAYMENT_METHOD_NONE_LABEL,
+                                    value: PAYMENT_METHOD_NONE,
+                                },
                                 {
                                     label: capitalize(
                                         PAYMENT_METHOD_STRIPE.toLowerCase(),
@@ -857,9 +861,6 @@ const Settings = (props: SettingsProps) => {
                                     }),
                                 )
                             }
-                            placeholderMessage={
-                                SITE_SETTINGS_PAYMENT_METHOD_NONE_LABEL
-                            }
                             disabled={!newSettings.currencyISOCode}
                         />