Merge pull request #954 from TheBlueMatt/2021-06-no-spurious-forward-fails

Consider channels "live" even if they are awaiting a monitor update

diff --cc lightning/src/ln/chanmon_update_fail_tests.rs
Simple merge

diff --cc lightning/src/ln/channel.rs
Simple merge

diff --cc lightning/src/ln/channelmanager.rs
Simple merge