Add github action CI badge

Author: grosbouddha

README.md

@@ -1,6 +1,8 @@
-Piskel
+Piskel 
 ======
 
+[![E2E Tests](https://github.com/piskelapp/piskel/actions/workflows/ci.yml/badge.svg?branch=master)](https://github.com/piskelapp/piskel/actions/workflows/ci.yml)
+
 Piskel is an easy-to-use sprite editor. It can be used to create game sprites, animations, pixel-art...
 It is the editor used in **[piskelapp.com](https://www.piskelapp.com)**.
 

tests/e2e/playwright/integration/settings/test-export-gif-scale.spec.ts

@@ -27,7 +27,7 @@ const base64_gif = [
   'mP+/lzZDXS8FKMAz6i3tyNU4k1NJx2xaS0AWGXf5eolzeGJWvCuKtYyAPPPkJUzYTkuvP69Qt8JhZStVNKkk0NWVlJzM0o',
   'YFvYHkZfP8HV3o3OtliK0/N5uXk/vtsv8De4Y3LYq8qFNwAAAABJRU5ErkJggg=='].join('');
 
-test('Test export png with scaling', async ({ page }) => {
+test('Test export gif with scaling', async ({ page }) => {
     await openEditor(page);
 
     await setPiskelFromImageSrc(page, base64_gif);