[SLO] Fix APM embeddable ids (elastic#264750)

## Summary

Closes elastic#264008

As part of the dashboards as code effort, elastic#254079 introduced a change by
which embeddable ids were changed. While most usages were properly
updated, a couple of hardcoded string references in the SLO plugin were
left unchanged. This is leading to issues where the APM embeddables in
the alert details page are failing to be displayed because the code is
unable to find the appropiate embeddable factory when searching by it's
old id.

In order to prevent issues like this in the future, I plan to do a
follow up PR providing a proper fix to this issue in a way that allows
the SLO plugin to consume the embeddable id constants defined in APM
instead of having to relay on redefining the strings values in both
plugins, which can lead to inconsistencies as this one. But, given the
timing with the 9.4 BC I've decided to go first for this quick-and-easy
approach of just changing the strings in the SLO plugin as well. While
this is not ideal code-wise it will allow us to have a low-risk fix in
time to be backported to 9.4 so we don't ship this view in a broken
state.

Author: AlejandroFrndz

x-pack/solutions/observability/plugins/slo/public/components/alert_details/components/custom_panels/apm/apm_alert_details.tsx

@@ -28,7 +28,7 @@ export function APMLatencyAlertDetails({
       <APMEmbeddableRoot
         slo={slo}
         dataTimeRange={dataTimeRange}
-        embeddableId={'APM_ALERTING_LATENCY_CHART_EMBEDDABLE'}
+        embeddableId={'apm_alerting_latency_chart'}
         alert={alert}
         rule={rule}
       />
@@ -37,7 +37,7 @@ export function APMLatencyAlertDetails({
           <APMEmbeddableRoot
             slo={slo}
             dataTimeRange={dataTimeRange}
-            embeddableId={'APM_ALERTING_THROUGHPUT_CHART_EMBEDDABLE'}
+            embeddableId={'apm_alerting_throughput_chart'}
             alert={alert}
             rule={rule}
           />
@@ -46,7 +46,7 @@ export function APMLatencyAlertDetails({
           <APMEmbeddableRoot
             slo={slo}
             dataTimeRange={dataTimeRange}
-            embeddableId={'APM_ALERTING_FAILED_TRANSACTIONS_CHART_EMBEDDABLE'}
+            embeddableId={'apm_alerting_failed_transactions_chart'}
             alert={alert}
             rule={rule}
           />
@@ -67,7 +67,7 @@ export function APMAvailabilityAlertDetails({
       <APMEmbeddableRoot
         slo={slo}
         dataTimeRange={dataTimeRange}
-        embeddableId={'APM_ALERTING_FAILED_TRANSACTIONS_CHART_EMBEDDABLE'}
+        embeddableId={'apm_alerting_failed_transactions_chart'}
         alert={alert}
         rule={rule}
       />
@@ -76,7 +76,7 @@ export function APMAvailabilityAlertDetails({
           <APMEmbeddableRoot
             slo={slo}
             dataTimeRange={dataTimeRange}
-            embeddableId={'APM_ALERTING_THROUGHPUT_CHART_EMBEDDABLE'}
+            embeddableId={'apm_alerting_throughput_chart'}
             alert={alert}
             rule={rule}
           />
@@ -85,7 +85,7 @@ export function APMAvailabilityAlertDetails({
           <APMEmbeddableRoot
             slo={slo}
             dataTimeRange={dataTimeRange}
-            embeddableId={'APM_ALERTING_LATENCY_CHART_EMBEDDABLE'}
+            embeddableId={'apm_alerting_latency_chart'}
             alert={alert}
             rule={rule}
           />

x-pack/solutions/observability/plugins/slo/public/components/alert_details/components/custom_panels/apm/embeddable_root.tsx

@@ -18,11 +18,9 @@ import { apmTransactionDurationIndicatorSchema } from '@kbn/slo-schema';
 import type { BurnRateAlert, BurnRateRule, TimeRange } from '../../../types';
 
 type EmbeddableId =
-  | 'APM_THROUGHPUT_CHART_EMBEDDABLE'
-  | 'APM_LATENCY_CHART_EMBEDDABLE'
-  | 'APM_ALERTING_FAILED_TRANSACTIONS_CHART_EMBEDDABLE'
-  | 'APM_ALERTING_LATENCY_CHART_EMBEDDABLE'
-  | 'APM_ALERTING_THROUGHPUT_CHART_EMBEDDABLE';
+  | 'apm_alerting_failed_transactions_chart'
+  | 'apm_alerting_latency_chart'
+  | 'apm_alerting_throughput_chart';
 
 export type APMTransactionDurationSLOResponse = GetSLOResponse & {
   indicator: APMTransactionDurationIndicator;