Redirects to Stripe Automatically if a level only accepts Checks

[JarrydLong]

Describe the bug
Have a Check Only level results in you being redirected to Stripe Checkout when hitting the submit button.

To Reproduce
Steps to reproduce the behavior:

1. Have Stripe (Checkout), the PayPal Express Add On and the Pay by Check Add On active
2. My level had an initial amount, expiration date, and the 'Allow Paying by Check' setting set to 'Users can only pay by check'
3. Checkout with this level
4. You'll automatically be redirected to Stripe Checkout

Screenshots

Expected behavior
You shouldn't be redirected to Stripe when a level only accepts payments via check

Isolating the problem (mark completed items with an [x]):

• I have deactivated other plugins and confirmed this bug occurs when only Paid Memberships Pro plugin is active.
• This bug happens with a default WordPress theme active, or Memberlite.
• I can reproduce this bug consistently using the steps above.

WordPress Environment

PMPro 3.3.2 PPExpress 0.7 Pay by Check 1.1