Alerting docs: update `Configure Alertmanagers` (#93712)
* Alerting docs: update `Configure Alertmanagers`
- clarify alertmanager types
- specify that each alertmanager manages its own alerting resources
* Update docs/sources/alerting/set-up/configure-alertmanager/index.md
Co-authored-by: brendamuir <100768211+brendamuir@users.noreply.github.com>
* Update docs/sources/alerting/set-up/configure-alertmanager/index.md
Co-authored-by: brendamuir <100768211+brendamuir@users.noreply.github.com>
* Update docs/sources/alerting/set-up/configure-alertmanager/index.md
Co-authored-by: brendamuir <100768211+brendamuir@users.noreply.github.com>
* use `Alertmanager` - capitalize the first letter
* Small copy changes
* Minor cosmetic updates to `Add an Alertmanager` section
* Update docs/sources/alerting/set-up/configure-alertmanager/index.md
Co-authored-by: brendamuir <100768211+brendamuir@users.noreply.github.com>
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Co-authored-by: brendamuir <100768211+brendamuir@users.noreply.github.com>
(cherry picked from commit 75900139ae)
Co-authored-by: Pepe Cano <825430+ppcano@users.noreply.github.com>