refactor(core): Move active workflows endpoints to a decorated controller class (no-changelog) (#8101)

This is a continuation of migrating all rest endpoints to decorated controller classes

packages/core/src/ActiveWorkflows.ts

@@ -1,3 +1,4 @@
+import { Service } from 'typedi';
 import { CronJob } from 'cron';
 
 import type {
@@ -22,10 +23,9 @@ import {
 
 import type { IWorkflowData } from './Interfaces';
 
+@Service()
 export class ActiveWorkflows {
-	private activeWorkflows: {
-		[workflowId: string]: IWorkflowData;
-	} = {};
+	private activeWorkflows: { [workflowId: string]: IWorkflowData } = {};
 
 	/**
 	 * Returns if the workflow is active in memory.