build: bump lnd to v0.21.0-beta.rc1

[calvinrzachman]

Update to latest lnd release.

NOTE: lnd v0.21's go.mod replaces lnd/queue => ./queue to carry unreleased backpressure code that lnd/actor depends on. Replaces don't propagate to consumers, so lndinit pins lnd/queue explicitly. The pin resolves to a lnd master pseudo-version rather than the v0.21 tag because Go couldn't resolve the submodule at dfb7d5782 directly. The queue API is the same between the two commits. We can remove this once a new release/version of queue package is cut upstream.

[calvinrzachman]

investigating CI failures. I think one is easy go version bump in tools dockerfile. The other is related to DB version and migrations 👀

[calvinrzachman]

Okay, looks like the testdata checked in to repo is db version 33. The db migration command has a check which prevents the command from running if the db version does not match the latest channeldb version. We've managed to dodge this type of CI failure until now but lnd v0.21 bumped LatestDBVersion from 33 → 35.

Made a little Go tool that opens the dbs and runs the migrations so I could checkpoint the files at the new db version. That has CI now passing.

➜  lndinit git:(lnd-v0.21.0-beta.rc1) ✗ go run ./cmd/migrate-testdata-db
channel.db migrated to version 35 at testdata/data/graph/regtest/channel.db
wtclient.db migrated to version 8 at testdata/data/graph/regtest/wtclient.db

We could commit the migration code and just run it when we bump lnd deps or another option would be to update the test code itself to run all the migrations from 33 --> current version which accrue upstream.