✅(tests) Add & adapt language tests

- Language will only be changed if different from current language
- Added test for custom translations

Signed-off-by: Robin Weber <weber@b1-systems.de>

src/frontend/apps/e2e/__tests__/app-impress/config.spec.ts

@@ -119,6 +119,26 @@ test.describe('Config', () => {
         .first(),
     ).toBeAttached();
   });
+
+  test('it checks theme_customization.translations config', async ({
+    page,
+  }) => {
+    await overrideConfig(page, {
+      theme_customization: {
+        translations: {
+          en: {
+            translation: {
+              Docs: 'MyCustomDocs',
+            },
+          },
+        },
+      },
+    });
+
+    await page.goto('/');
+
+    await expect(page.getByText('MyCustomDocs')).toBeAttached();
+  });
 });
 
 test.describe('Config: Not loggued', () => {