Fix cmd run_all bg error

[The-Loeki]

What does this PR do?

Fix erroneous logging/retcode errors when bg=True in cmd.run(_all)

What issues does this PR fix or reference?

relates to #39980
fixes #42932

Previous Behavior

root@w1:~# salt-call -l debug --out=raw cmd.run_all bg=True 'sleep 5' 
[DEBUG   ] LazyLoaded cmd.run_all
[DEBUG   ] LazyLoaded config.get
[INFO    ] Executing command 'sleep 5' in directory '/root'. Executing command in the background, no output will be logged.
[ERROR   ] Command 'sleep 5' failed with return code: None
[DEBUG   ] LazyLoaded raw.output
{'local': {'pid': 18860, 'retcode': None, 'stderr': '', 'stdout': None}}

New Behavior

root@w1:~# salt-call -l debug --out=raw cmd.run_all bg=True 'sleep 5' 
[DEBUG   ] LazyLoaded config.get
[INFO    ] Executing command 'sleep 5' in directory '/root'. Executing command in the background, no output will be logged.
[DEBUG   ] LazyLoaded raw.output
{'local': {'pid': 17579, 'retcode': None, 'stderr': '', 'stdout': None}}

[rallytime]

@The-Loeki In order to get this into the oxygen RC, it needs to be submitted directly there. However, it's not cherry-picking cleanly. Can you make this fix against the oxygen.rc1 branch as well if you'd like the fix in oxygen.rc1? Thanks!