Removed the use of any and enabled the rule in eslint.

Now according to me the conversion is final.
Testing is required.

overlord/src/app/settings/maintenance-resolver.service.ts

@@ -7,10 +7,10 @@ import { SettingsService } from './settings.service';
 @Injectable({
   providedIn: 'root',
 })
-export class MaintenanceResolver implements Resolve<any> {
+export class MaintenanceResolver implements Resolve<{ enabled: boolean; user: string }> {
   constructor(private ser: SettingsService) {}
 
-  resolve(): Observable<any> {
+  resolve(): Observable<{ enabled: boolean; user: string }> {
     return this.ser.getMaintenance();
   }
 }