[APM] Add default message to alerts.

[cauemarcondes]

The alerts API defines a prop called defaultActionMessage to set a default message for the user.

• Add defaultActionMessage to the alerts available.

@formgeist @bmorelli25 I could use some help to define a message for each alert we have:

• Transaction duration threshold
• Transaction duration anomaly
• Transaction error rate
• Error count

Example placeholder message templates from other alert types

Uptime anomaly alert

Abnormal ({{state.severity}} level) response time detected on {{state.monitor}} with url {{{state.monitorUrl}}} at {{state.anomalyStartTimestamp}}. Anomaly severity score is {{state.severityScore}}.
Response times as high as {{state.slowestAnomalyResponse}} have been detected from location {{state.observerLocation}}. Expected response time is {{state.expectedResponseTime}}.

Inventory threshold alert

{{alertName}} - {{context.group}} is in a state of {{context.alertState}}

Reason:
{{context.reason}}

[elasticmachine]

Pinging @elastic/apm-ui (Team:apm)

[formgeist]

@cauemarcondes Just to clarify - are we able to bucket the services together into a single alert? I assume this is something we should keep in mind when creating the placeholder copy.

[sorenlouv]

@cauemarcondes Can you make a draft PR with these changes, and the initial copy for the default messages? That'll make it easier for @formgeist / @bmorelli25 to see what's possible.

[cauemarcondes]

@formgeist no, for 7.10 we're sending unique alerts per service/environment/transaction_type.

[cauemarcondes]

@cauemarcondes Can you make a draft PR with these changes, and the initial copy for the default messages? That'll make it easier for @formgeist / @bmorelli25 to see what's possible.

Yes, working on that @sqren 😁

[cauemarcondes]

And is good to keep in mind that the default message is not supported by all actions.

[sorenlouv]

And is good to keep in mind that the default message is not supported by all actions.

I think @pmuellr is working on that :)

[formgeist]

I've added some placeholder examples to the description. They're not really in the same "language", but I want to strive for that in ours at least. Then we can make them more consistent with the other Observability apps.