Fix for double "Add new card" button in NativeScript Stripe

index.android.ts

export class StripeStandardPaymentSession {
    // all the code...

    constructor(_page: Page, public customerSession: StripeStandardCustomerSession, amount: number, public currency: string, public listener: StripeStandardPaymentListener, prefilledAddress?: Address) {
		let builder = StripeStandardConfig.shared.nativeBuilder;
        // ...

		const allowPaymentMethodTypes = new java.util.ArrayList();
        // Added HashSet, to keep the list unique
        const allowPaymentMethodTypesSet = new java.util.HashSet();

		StripeStandardConfig.shared.allowedPaymentMethodTypes.forEach((type) => {
			switch (type) {
				case StripeStandardPaymentMethodType.Card:
					allowPaymentMethodTypes.add(com.stripe.android.model.PaymentMethod.Type.Card);
					break;
				case StripeStandardPaymentMethodType.Fpx:
					allowPaymentMethodTypes.add(com.stripe.android.model.PaymentMethod.Type.Fpx);
					break;
			}
		});
        // HashSet needs to be converted to ArrayList to continue
		allowPaymentMethodTypes.addAll(allowPaymentMethodTypesSet);
        // ~~~ OR ~~~ 
        // this next line can be removed, there is no equivalent in index.ios.ts, and it 
        // works just the same even without this call to setPaymentMethodTypes method.
		builder.setPaymentMethodTypes(allowPaymentMethodTypes);

        // ...
	}

    // ...
}