Prepare release 0.41.0 (#1328)

[skip ci]

release rivertype/v0.41.0

release rivershared/v0.41.0

release riverdriver/v0.41.0

release riverdriver/riversqlite/v0.41.0

release riverdriver/riverpgxv5/v0.41.0

release riverdriver/riverdatabasesql/v0.41.0

release cmd/river/v0.41.0

Prepare release 0.40.0 (#1295)

Prepare release 0.40.0. This is actually a pretty big one that includes
a lot of stuff and a migration.

[skip ci]

release rivertype/v0.40.0