rfq: fix potential nil pointer panic #3530

Job	Run time
Docker build check	3m 44s
cross compilation	11m 50s
Format check	25s
Compilation check	1m 35s
run itests	11m 23s
run itests postgres	19m 26s
migration version check	13s
Lint check	2m 41s
go mod check	21s
RPC check	1m 8s
run LiT tests	14m 16s
sample configuration check	43s
Sqlc check	2m 42s
test vector check	1m 3s
run unit tests (unit-race)	11m 25s
run unit tests (unit-cover)	4m 23s
run unit tests (unit dbbackend=postgres)	6m 14s
finish	3s
	1h 33m 35s

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