Datadog integration for events

**Is your feature request related to a problem? Please describe.**
Correlating metrics to events could be made easier.

**Describe the solution you'd like**
The `/#/events` page in the CockroachDB web UI has very useful data for example config changes and schema changes. Pushing these events to Datadog would allow to embed these events in metric graphs for much easier correlation. In addition to events already on this page, we might consider adding events for every time a job is created (e.g. backup jobs).

**Describe alternatives you've considered**
Viewing the events separately from metrics is useful but takes more time and requires moving between Datadog and the CockroachDB console. Currently events are also not stored indefinitely or searchable.

**Additional context**
For reference an example Datadog graph with events embedded in red

Jira issue: CRDB-26156