multi: fix `staticcheck` flags #2806

Job	Run time
SQL compilation check	8s
run unit-test sqlite3 race	8m 38s
go mod check	11m 45s
run LiT itests	5m 16s
build and lint code	4m 56s
run unit-test postgres race	10m 33s
verify that auto-generated documentation is up-to-date	33s
RPC compilation check	1m 31s
run LiT unit tests	5m 53s
	49m 13s

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