Monitoring tutorial overhaul

Either we need to switch to EU's influxdb role where they use a container to deploy influxdb

Or we need to replace it, because version 2 is too different. Perhaps we replace it with Prometheus.

Additionally:
- telegraf should come before grafana
- we should investigate the output
- then set up grafana after

```yaml
---
- hosts: all
become: true
roles:
- prometheus.prometheus.prometheus
vars:
prometheus_scrape_configs:
- job_name: "prometheus"
metrics_path: "{{ prometheus_metrics_path }}"
static_configs:
- targets:
- "{{ ansible_fqdn | default(ansible_host) | default('localhost') }}:9090"
- job_name: "gtn"
metrics_path: "/training-material/metrics"
scheme: https
static_configs:
- targets:
- "training.galaxyproject.org"
- job_name: "tiaas"
metrics_path: "/tiaas/metrics"
scheme: https
static_configs:
- targets:
- "usegalaxy.eu"
- "usegalaxy.fr"
- "usegalaxy.org"
- "usegalaxy.org.au"
```

this works OK, once the collection is installed:

```console
ansible-galaxy collection install prometheus.prometheus -p collections
```