Fix following groups + Add interface to manage followers

Signed-off-by: Thomas Citharel <tcit@tcit.fr>

js/src/types/actor/group.model.ts

@@ -19,6 +19,7 @@ export interface IGroup extends IActor {
   organizedEvents: Paginate<IEvent>;
   physicalAddress: IAddress;
   openness: Openness;
+  manuallyApprovesFollowers: boolean;
 }
 
 export class Group extends Actor implements IGroup {
@@ -45,6 +46,8 @@ export class Group extends Actor implements IGroup {
 
   physicalAddress: IAddress = new Address();
 
+  manuallyApprovesFollowers = true;
+
   patch(hash: IGroup | Record<string, unknown>): void {
     Object.assign(this, hash);
   }