fix unit test

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

@@ -176,7 +176,7 @@ describe('PostfachFormComponent', () => {
     function createProblemDetailForAbsenderName(): ProblemDetail {
       return {
         ...createProblemDetail(),
-        'invalid-params': [{ ...createInvalidParam(), name: 'settingsBody.absender.name' }],
+        'invalid-params': [{ ...createInvalidParam(), name: 'settingBody.absender.name' }],
       };
     }