test: Add validation for error handling in custom components and utility function (#6634)

✨ (validate-raise-errors-components.spec.ts): add test to validate error messages on popups when an error is raised in custom components
📝 (add-custom-component.ts): add utility function to add custom components in tests for easier testing and validation of error messages

src/frontend/tests/utils/add-custom-component.ts

@@ -0,0 +1,12 @@
+import { Page } from "playwright/test";
+
+export const addCustomComponent = async (page: Page) => {
+  let numberOfCustomComponents = 0;
+
+  while (numberOfCustomComponents === 0) {
+    await page.getByTestId("sidebar-custom-component-button").click();
+    numberOfCustomComponents = await page
+      .locator('[data-testid="title-Custom Component"]')
+      .count();
+  }
+};