[APM] Ensure telemetry data matches SO/telemetry mapping

Closes #61802.

Author: dgieselaar

x-pack/plugins/apm/server/lib/apm_telemetry/collect_data_telemetry/tasks.ts

@@ -236,7 +236,7 @@ export const tasks: TelemetryTask[] = [
         .map(part => Number(part));
 
       return {
-        versions: {
+        version: {
           apm_server: {
             major,
             minor,

x-pack/plugins/apm/server/lib/apm_telemetry/types.ts

@@ -18,7 +18,7 @@ export type TimeframeMapAll = Pick<TimeframeMap, 'all'>;
 export type APMDataTelemetry = DeepPartial<{
   has_any_services: boolean;
   services_per_agent: Record<AgentName, number>;
-  versions: {
+  version: {
     apm_server: {
       minor: number;
       major: number;