Reword "trade started" popup messages per suggestion

[ghost]

This PR implements @m52go's suggested simplification.

^ there is a lot of text on this screen...this reduces the chance that the user reads any of it.
I'm not sure the parts on multiple confirmations, bank details, copy/paste, etc. are that important.
Suggestion to simplify:

Your trade has reached at least 1 blockchain confirmation.
Please pay 303 EUR via the specified payment method to the BTC seller. You'll find the seller's account details on the next screen.
Important: when making the payment, leave the "reason for payment" field empty. DO NOT put the trade ID or any other text like 'bitcoin', 'BTC', or 'Bisq'.
If your bank charges you any fees to make the transfer, you are responsible for paying those fees.

#5080 (comment)

And

I agree, but I would prefer to keep that for another PR. There are more popup text to improve but as the text is composed of several blocks depending on payment method its also not that trivial and need then better testing with the diff. payment methods.
Any dev who wants to pick that up?

#5080 (comment)

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Here is a set of screenshots showing how each popup looks: trade_popups.pdf. It includes FasterPayments, Cash Desposit, Moneygram, HalCash, Altcoins, F2F, Zelle, Transferwise, Amazon, USPSMO, Sepa.

Here's one example:

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Please note I had to implement on PR #5080, so those commits are also included here. I presume #5080 will be merged prior to this. Hopefully git will handle things intelligently.

[Conza88]

Typo for “youll”.

I’d also be keen to have: #5080 (comment)

[ghost]

@m52go 👆
@Conza88 thanks for finding the typo.

[ripcurlx]

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