rfq: fix precision issue in HTLC compliance check #3406

Job	Run time
Format check	27s
Compilation check	56s
cross compilation	4m 31s
Docker build check	3m 44s
run itests	8m 44s
run itests postgres	17m 12s
Lint check	2m 54s
migration version check	17s
go mod check	27s
RPC check	1m 20s
run LiT tests	10m 49s
sample configuration check	40s
test vector check	50s
Sqlc check	2m 41s
run unit tests (unit-race)	7m 24s
run unit tests (unit-cover)	4m 23s
run unit tests (unit dbbackend=postgres)	3m 18s
finish	4s
	1h 10m 41s

Provide feedback