OZG-4995 Set `submitInProgress$` during construction

alfa-client/libs/admin-settings/src/lib/organisationseinheit/organisationseinheit-container/organisationseinheit-form/organisationseinheit-form.component.ts

-import { AfterViewInit, Component, ElementRef, OnInit, ViewChild } from '@angular/core';
+import { AfterViewInit, Component, ElementRef, ViewChild } from '@angular/core';
 import { OrganisationseinheitFormservice } from './organisationseinheit.formservice';
 import { Observable, of, tap } from 'rxjs';
 import { Organisationseinheit } from '../../../user/user.model';
@@ -8,7 +8,7 @@ import { Organisationseinheit } from '../../../user/user.model';
   templateUrl: './organisationseinheit-form.component.html',
   providers: [OrganisationseinheitFormservice],
 })
-export class OrganisationseinheitFormComponent implements OnInit, AfterViewInit {
+export class OrganisationseinheitFormComponent implements AfterViewInit {
   static CREATE_LABEL: string = 'Neue Organisationseinheit anlegen';
   static EDIT_LABEL: string = 'Organisationseinheit bearbeiten';
 
@@ -17,7 +17,7 @@ export class OrganisationseinheitFormComponent implements OnInit, AfterViewInit
   @ViewChild('OrganisationseinheitDialog') private dialogRef: ElementRef<HTMLDialogElement>;
   dialog: HTMLDialogElement;
 
-  submitInProgress$: Observable<boolean>;
+  submitInProgress$: Observable<boolean> = of(false);
 
   label: string;
 
@@ -27,10 +27,6 @@ export class OrganisationseinheitFormComponent implements OnInit, AfterViewInit
     this.dialog = this.dialogRef.nativeElement;
   }
 
-  ngOnInit(): void {
-    this.submitInProgress$ = of(false);
-  }
-
   public submit() {
     this.submitInProgress$ = this.formService
       .submit()

alfa-client/libs/admin-settings/src/lib/postfach/postfach-container/postfach-form/postfach-form.component.ts

-import { Component, Input, OnInit } from '@angular/core';
+import { Component, Input } from '@angular/core';
 import { PostfachFormService } from './postfach.formservice';
 import { isNotNil, ProblemDetail, StateResource } from '@alfa-client/tech-shared';
 import { PostfachResource } from '../../postfach.model';
@@ -9,8 +9,8 @@ import { map, Observable, of } from 'rxjs';
   templateUrl: './postfach-form.component.html',
   providers: [PostfachFormService],
 })
-export class PostfachFormComponent implements OnInit {
-  submitInProgress$: Observable<boolean>;
+export class PostfachFormComponent {
+  submitInProgress$: Observable<boolean> = of(false);
 
   @Input() set postfachStateResource(stateResource: StateResource<PostfachResource>) {
     this.updatePostfachResource(stateResource.resource);
@@ -26,10 +26,6 @@ export class PostfachFormComponent implements OnInit {
 
   constructor(public formService: PostfachFormService) {}
 
-  ngOnInit(): void {
-    this.submitInProgress$ = of(false);
-  }
-
   public submit(): void {
     this.submitInProgress$ = this.formService
       .submit()