Add support for 13 triggers

[tlefevre-stripe]

Reviewers

r? @stripe/developer-products
cc @stripe/developer-products

Summary

This PR adds support for 13 triggers:

• checkout.session.expired
• charge.dispute.closed
• charge.dispute.updated
• credit_note.created
• credit_note.updated
• credit_note.voided
• payment_method.updated
• payment_intent.processing
• transfer.created
• transfer.reversed
• transfer.updated
• customer_cash_balance_transaction.created
• cash_balance.funds_available

And also fixed a typo for the charge.dispute.created event.

Note that in the triggers.go file, the linter automatically added an extra space in all the triggers because customer_cash_balance_transaction.created is too long.