Fixes Proc.new deprecation warning on Ruby 2.7
Fixes Proc.new deprecation warning on Ruby 2.7

Using `Proc.new` to capture the block is deprecated. I believe this
supports the intended behavior or accepting either an object that
responds to #call or a block.

integrallis/stripe_event,fullfabric/stripe_event,integrallis/stripe_event,fullfabric/stripe_event