* more reasonable default expiry
600 = 10 minutes which is a pretty short amount of time, for example when using lnbits fundingsource inside lnbits itself it would fail if you do a submarine swap or anything involved with hold invoices
i think 3600 = 1 hour should not make a difference in performance and is a way more reasonable expiry
* change default in .env.example
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Co-authored-by: callebtc <93376500+callebtc@users.noreply.github.com>