feat(test): use common function to launch the browser

test/api/CharWidth.api.ts

@@ -3,7 +3,7 @@
  * @license MIT
  */
 
-import { pollFor, openTerminal, getBrowserType } from './TestUtils';
+import { pollFor, openTerminal, launchBrowser } from './TestUtils';
 import { Browser, Page } from 'playwright';
 
 const APP = 'http://127.0.0.1:3001/test';
@@ -15,10 +15,7 @@ const height = 600;
 
 describe('CharWidth Integration Tests', function(): void {
   before(async function(): Promise<any> {
-    const browserType = getBrowserType();
-    browser = await browserType.launch({
-      headless: process.argv.indexOf('--headless') !== -1
-    });
+    browser = await launchBrowser();
     page = await (await browser.newContext()).newPage();
     await page.setViewportSize({ width, height });
     await page.goto(APP);