ci: Speed up playwright tests (#1357)

Author: askoufis

.github/workflows/validate.yml

@@ -70,7 +70,7 @@ jobs:
         run: pnpm test:unit
   playwright:
     name: Playwright tests
-    runs-on: macos-11
+    runs-on: macos-14
     env:
       CI: true
     steps:

playwright.config.ts

@@ -1,4 +1,5 @@
 import { PlaywrightTestConfig, defineConfig } from '@playwright/test';
+import { cpus } from 'os';
 
 // Prevent Vite from attempting to clear the screen
 process.stdout.isTTY = false;
@@ -12,6 +13,7 @@ const config: PlaywrightTestConfig = defineConfig({
       maxDiffPixelRatio: 0.02,
     },
   },
+  workers: process.env.CI ? cpus().length : undefined,
   snapshotDir: 'tests/e2e/snapshots',
   // put all snapshots in one directory
   // https://playwright.dev/docs/api/class-testconfig#test-config-snapshot-path-template