multi: update to fn v2 #16640

Job	Run time
cross compilation	12m 10s
check commits	10m 15s
lint code	5m 58s
check pinned dependencies (google.golang.org/grpc v1.59.0)	5s
run macOS itest	0s
check pinned dependencies (github.com/golang/protobuf v1.5.3)	4s
check release notes updated	0s
RPC and mobile compilation check	6m 7s
sample configuration check	4m 23s
Sqlc check	5m 0s
run ubuntu itests	0s
run unit tests (btcd unit-cover)	12m 10s
run windows itest	0s
run unit tests (unit tags="kvdb_etcd")	12m 9s
run unit tests (unit tags="kvdb_postgres")	12m 11s
run unit tests (unit tags="kvdb_sqlite")	12m 10s
run unit tests (btcd unit-race)	12m 10s
run unit tests (unit-module)	4m 35s
finish	7s
	1h 49m 34s

Provide feedback