Link monzo account into share/stock trading accounts

Enable integration between Monzo bank accounts and share trading accounts with companies like DeGiro, so that Monzo is able to get a better financial health picture of a customer when making decisions on things such as overdrafts. Other financial institutions currently don’t take this into account properly when assessing things such as credit scores, resulting in a mispricing of certain services or the denial of financial products to customers. This would also enable customers to get better value from Monzo as a financial portal where they can see the full extent of their personal finances.