Fix persistence of empty comment

apps/client/eslint.config.cjs

@@ -52,6 +52,7 @@ module.exports = [
         'error',
         {
           ignorePrimitives: {
+            boolean: true,
             string: true
           }
         }

apps/client/src/app/pages/accounts/create-or-update-account-dialog/create-or-update-account-dialog.component.ts

@@ -198,7 +198,7 @@ export class GfCreateOrUpdateAccountDialogComponent {
   protected async onSubmit() {
     const account: CreateAccountDto | UpdateAccountDto = {
       balance: this.accountForm.get('balance')?.value,
-      comment: this.accountForm.get('comment')?.value ?? null,
+      comment: this.accountForm.get('comment')?.value || null,
       currency: this.accountForm.get('currency')?.value,
       id: this.accountForm.get('accountId')?.value,
       name: this.accountForm.get('name')?.value,

apps/client/src/app/pages/portfolio/activities/create-or-update-activity-dialog/create-or-update-activity-dialog.component.ts

@@ -471,7 +471,7 @@ export class GfCreateOrUpdateActivityDialogComponent {
       accountId: this.activityForm.get('accountId')?.value,
       assetClass: this.activityForm.get('assetClass')?.value,
       assetSubClass: this.activityForm.get('assetSubClass')?.value,
-      comment: this.activityForm.get('comment')?.value ?? null,
+      comment: this.activityForm.get('comment')?.value || null,
       currency: this.activityForm.get('currency')?.value,
       customCurrency: this.activityForm.get('currencyOfUnitPrice')?.value,
       dataSource: ['FEE', 'INTEREST', 'LIABILITY', 'VALUABLE'].includes(