Hide payment type toggle for cash only membership tiers minds#2259

Closes minds#2259

@markeharding can you test the cash flow when you review? Looks to all work fine but I cannot add a card to the sandbox at the moment.

Here are two tiers:

• cash or tokens: https://fix-no-token-paywall-minds-2259.minds.io/newsfeed/1231230985190772741
• cash only: https://fix-no-token-paywall-minds-2259.minds.io/newsfeed/1231230917331128323