Replace deprecated apm settings

tracing.apm.* settings were deprecated in 8.14.0 in favor of the new
telemetry.* settings. Use the new settings starting with 8.14.0.

Old settings will be removed in 9.0.

internal/stack/_static/elasticsearch.yml.tmpl

@@ -29,7 +29,13 @@ script.context.template.cache_max_size: 2000
 
 {{ $apm_enabled := fact "apm_enabled" }}
 {{ if eq $apm_enabled "true" }}
+{{ if semverLessThan $version "8.14.0" }}
 tracing.apm.enabled: true
 tracing.apm.agent.server_url: "http://fleet-server:8200"
 tracing.apm.agent.environment: "dev"
+{{- else -}}
+telemetry.tracing.enabled: true
+telemetry.agent.server_url: "http://fleet-server:8200"
+telemetry.agent.environment: "dev"
+{{- end -}}
 {{- end -}}