Galaxy services fail to start

## Running Ansible playbook left out the last steps

I'm running the [Ansible playbook](https://training.galaxyproject.org/training-material/topics/admin/tutorials/ansible-galaxy/tutorial.html) for setting up Galaxy, on a Rocky Linux 9 system. The playbook ended without error but didn't finish the last steps:
```
...

TASK [galaxyproject.miniconda : Create Galaxy conda env] ********************************************************************************************************************************************************
skipping: [scc-mem01-10G]

PLAY RECAP ******************************************************************************************************************************************************************************************************
scc-mem01-10G : ok=72 changed=1 unreachable=0 failed=0 skipped=57 rescued=0 ignored=0
```
It also seems to have not started the services related to Galaxy. Running `systemctl status galaxyctl` doesn't find the service.
```
Unit galaxyctl.service could not be found.
```

## Galaxy services are not found, until explicitly started, and then fail

Running `galaxyctl status` returns
```
Error: Invalid value for '-c' / '--config-file': File '/srv/galaxy/config/galaxy.yml' is not readable.
```
Running `sudo /usr/local/bin/galaxyctl status` returns
```
Dynamic handlers are configured in Gravity but Galaxy is not configured to assign jobs to handlers dynamically, so these handlers will not handle jobs. Set the job handler assignment method in the Galaxy job configuration to `db-skip-locked` or `db-transaction-isolation` to fix this.
UNIT LOAD ACTIVE SUB DESCRIPTION
● galaxy-celery-beat.service loaded failed failed Galaxy celery-beat
● galaxy-celery.service loaded failed failed Galaxy celery
● galaxy-gunicorn.service loaded failed failed Galaxy gunicorn
● galaxy-handler@0.service loaded failed failed Galaxy handler (process 0)
● galaxy-handler@1.service loaded failed failed Galaxy handler (process 1)
galaxy.target loaded active active Galaxy

LOAD = Reflects whether the unit definition was properly loaded.
ACTIVE = The high-level unit activation state, i.e. generalization of SUB.
SUB = The low-level unit activation state, values depend on unit type.
6 loaded units listed.
To show all installed unit files use 'systemctl list-unit-files'.
```
And going into detail for the services (e.g., with `systemctl status galaxy-celery-beat`) I get
```
× galaxy-celery-beat.service - Galaxy celery-beat
Loaded: loaded (/etc/systemd/system/galaxy-celery-beat.service; disabled; preset: disabled)
Active: failed (Result: exit-code) since Fri 2025-03-21 15:37:36 CET; 17min ago
Duration: 14ms
Process: 1094127 ExecStart=/srv/galaxy/venv/bin/galaxyctl --config-file /srv/galaxy/config/galaxy.yml exec _default_ celery-beat (code=exited, status=203/EXEC)
Main PID: 1094127 (code=exited, status=203/EXEC)
CPU: 4ms

Mar 21 15:37:36 scc-mem01-10G systemd[1]: galaxy-celery-beat.service: Main process exited, code=exited, status=203/EXEC
Mar 21 15:37:36 scc-mem01-10G systemd[1]: galaxy-celery-beat.service: Failed with result 'exit-code'.
Mar 21 15:37:36 scc-mem01-10G systemd[1]: galaxy-celery-beat.service: Scheduled restart job, restart counter is at 5.
Mar 21 15:37:36 scc-mem01-10G systemd[1]: Stopped Galaxy celery-beat.
Mar 21 15:37:36 scc-mem01-10G systemd[1]: galaxy-celery-beat.service: Start request repeated too quickly.
Mar 21 15:37:36 scc-mem01-10G systemd[1]: galaxy-celery-beat.service: Failed with result 'exit-code'.
Mar 21 15:37:36 scc-mem01-10G systemd[1]: Failed to start Galaxy celery-beat.
```

## With the virtual environment

Activating the virtual environment at `/srv/galaxy/venv` and running `galaxyctl status` I get
```
Error: No configured Galaxy instances
```