Avoid that buyer switches back to trade step 2 at startup after payment confirmed

[chimp1984]

Fixes #4864

When seller if offline we resend the CounterCurrencyTransferStartedMessage at startup.
That caused the trade state set to BUYER_SENT_FIAT_PAYMENT_INITIATED_MSG and then after
the msg was stored in mailbox to BUYER_STORED_IN_MAILBOX_FIAT_PAYMENT_INITIATED_MSG.
Those 2 msg trigger diff. UI states which led to the UI glitch that the UI moved to
step 2 and then to step 3 which was correct but confusing to the user.

Now we only apply BUYER_SENT_FIAT_PAYMENT_INITIATED_MSG is trade state ordinal is
smaller avoiding that UI glitch.

This is not a critical bug fix so open to maintainers to add it to 1.5.1. But I think its also very low risk and easy to review and test.

[chimp1984]

How to test it?

• Create a trade and close seller after take offer.
• Create a new block, buyer gets to step 2
• Buyer confirms payment sent. Msg is stored in mailbox, buyer is at step 3
• Restart buyer and leave screen at open trades. You will see at start that it starts with step2, sends the msg again and then goes to step 3. This automatic switch from step 2 to step 3 is confusing to users and this PR fixes that.

[ripcurlx]

ACK

Fixes the problem for me on Regtest