lnrpc+cli: add optional raw tx hex resp to `bumpfee` cmd and rpc #17144

Job	Run time
check commits	2m 57s
Sqlc check	2m 53s
cross compilation (i386, freebsd-386 linux-386 windows-386)	2m 54s
lint code	2m 55s
cross compilation (amd64, darwin-amd64 freebsd-amd64 linux-amd64 netbsd-amd64 openbsd-amd64 windo...	2m 54s
RPC and mobile compilation check	2m 23s
sample configuration check	13s
cross compilation (arm, darwin-arm64 freebsd-arm linux-armv6 linux-armv7 linux-arm64 windows-arm)	2m 53s
run unit tests (btcd unit-cover)	1s
basic itests (btcd, backend=btcd cover=1)	1s
run unit tests (unit tags="kvdb_etcd")	1s
itests (bitcoind-rpcpolling, backend="bitcoind rpcpolling")	1s
basic itests (bitcoind, backend=bitcoind cover=1)	31s
run unit tests (unit tags="kvdb_postgres")	1s
itests (bitcoind-etcd, backend=bitcoind dbbackend=etcd)	1s
basic itests (bitcoind-notxindex, backend="bitcoind notxindex")	1s
run unit tests (unit tags="kvdb_sqlite")	1s
itests (bitcoind-sqlite, backend=bitcoind dbbackend=sqlite)	1s
basic itests (neutrino, backend=neutrino cover=1)	1s
run unit tests (btcd unit-race)	1s
itests (bitcoind-sqlite-nativesql, backend=bitcoind dbbackend=sqlite nativesql=true)	1s
run unit tests (unit-module)	1s
itests (bitcoind-postgres, backend=bitcoind dbbackend=postgres)	1s
itests (bitcoind-postgres-nativesql, backend=bitcoind dbbackend=postgres nativesql=true)	1s
check pinned dependencies (google.golang.org/grpc v1.59.0)	1s
check pinned dependencies (github.com/golang/protobuf v1.5.3)	1s
macOS itest	1s
check release notes updated	1s
windows itest	1m 4s
finish	5s
	22m 1s

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