Fix crash when a chat channel references an invalid chat action set

When there are no chat action sets or an action set has been deleted, bad
things would happen (e.g. segfault) when listing chat channels.
15 jobs for dailybuild_linux-x64 in 60 minutes and 5 seconds (queued for 14 seconds)
Status Job ID Name Coverage
  Build
passed #37689
FreeBSD
jsdoor-freebsd

00:03:49

passed #37690
Linux
jsdoor-linux

00:06:35

passed #37692
FreeBSD
jsdoor-windows

00:01:53

passed #37684
FreeBSD
sbbs-freebsd

00:05:18

passed #37678
Linux
sbbs-linux

00:09:50

failed #37681
Windows
sbbs-windows

01:00:01

passed #37691
FreeBSD
sexpots-freebsd

00:00:12

passed #37679
Linux
sexpots-linux

00:00:23

passed #37682
Windows
sexpots-windows

00:00:22

passed #37683
Windows
svdm-windows

00:00:21

passed #37687
FreeBSD
syncdraw-freebsd

00:00:22

passed #37688
Linux
syncdraw-linux

00:01:04

passed #37685
FreeBSD
syncterm-freebsd

00:00:59

passed #37680
Linux
syncterm-linux

00:02:56

passed #37686
FreeBSD
syncterm-windows

00:01:45

 
Name Stage Failure
failed
sbbs-windows Build The script exceeded the maximum execution time set for the job
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Building the projects in this solution one at a time. To enable parallel build, please add the "-m" switch.
Build started 8/4/2022 5:25:42 AM.
ERROR: Job failed: execution took longer than 1h0m0s seconds