Merge branch 'update-script' into 'master'

add script to update/maintain channel lists

See merge request !5
3 jobs for master in 10 minutes and 46 seconds (queued for 3 seconds)
latest
Status Job ID Name Coverage
  Build And Test
passed #247713
ligo-channel-completion:buster

00:01:21

passed #247715
ligo-channel-completion:jessie

00:10:45

passed #247714
ligo-channel-completion:stretch

00:01:12