sample-lnd.conf: fix typo #11614

Job	Run time
RPC and mobile compilation check	2m 52s
lint code	8m 22s
check commits	39s
Sqlc check	22s
check pinned dependencies (google.golang.org/grpc v1.53.0)	4s
cross compilation	40m 0s
check pinned dependencies (github.com/golang/protobuf v1.5.2)	11s
sample configuration check	1m 58s
run ubuntu itests	0s
run unit tests (btcd unit-cover)	21m 44s
run windows itest	0s
run unit tests (unit tags="kvdb_etcd")	19m 56s
run unit tests (unit tags="kvdb_postgres")	18m 12s
check release notes updated	0s
run unit tests (unit tags="kvdb_sqlite")	20m 4s
run unit tests (btcd unit-race)	40m 32s
run unit tests (unit-module)	2m 30s
	2h 57m 26s

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