Extract Expense Details from Gmail to Google Sheets

# B. Deal with the data
1. Multiple payment info in one mail: input the "sender" of the emails that contain more than one payment info. e.g. credit card daily spend notification
2. One payment info in one mail: input the "sender" of the emails that contain only one payment info. e.g. instant credit card spend notification
3. Invoices: input the mails that contain one invoice in one mail