docs(ci): update ci docs to emphasize gh action (#1964)

Author: arjunattam

docs/ci.md

@@ -1,26 +1,34 @@
-# Continuous integration
+# Continuous Integration
 
 Playwright tests can be executed to run on your CI environments. To simplify this, we have created sample configurations for common CI providers that can be used to bootstrap your setup.
 
-#### Contents
-- [Docker](#docker)
+<!-- GEN:toc -->
 - [GitHub Actions](#github-actions)
+- [Docker](#docker)
 - [Azure Pipelines](#azure-pipelines)
 - [Travis CI](#travis-ci)
 - [CircleCI](#circleci)
 - [AppVeyor](#appveyor)
+<!-- GEN:stop -->
 
 Broadly, configuration on CI involves **ensuring system dependencies** are in place, **installing Playwright and browsers** (typically with `npm install`), and **running tests** (typically with `npm test`). Windows and macOS build agents do not require any additional system dependencies. Linux build agents can require additional dependencies, depending on the Linux distribution.
 
-<br/>
+## GitHub Actions
 
-## Docker
+The [Playwright GitHub Action](https://github.com/microsoft/playwright-github-action) can be used to run Playwright tests on GitHub Actions.
 
-We have a [pre-built Docker image](docker/README.md) which can either be used directly, or as a reference to update your existing Docker definitions.
+```yml
+steps:
+  - uses: microsoft/playwright-github-action@v1
+  - name: Run your tests
+    run: npm test
+```
 
-## GitHub Actions
+We run [our tests](/.github/workflows/tests.yml) on GitHub Actions, across a matrix of 3 platforms (Windows, Linux, macOS) and 3 browsers (Chromium, Firefox, WebKit).
+
+## Docker
 
-We run [our tests](/.github/workflows/tests.yml) on GitHub Actions, across a matrix of 3 platforms (Windows, Linux, macOS) and 3 browsers (Chromium, Firefox, WebKit). Use the [microsoft/playwright-github-action](https://github.com/microsoft/playwright-github-action) to bootstrap your GitHub Actions configuration.
+We have a [pre-built Docker image](docker/README.md) which can either be used directly, or as a reference to update your existing Docker definitions.
 
 ## Azure Pipelines
 
@@ -38,4 +46,4 @@ We run our tests on CircleCI, with our [pre-built Docker image](docker/README.md
 
 ## AppVeyor
 
-We run our tests on Windows agents in AppVeyor. Use our [AppVeyor configuration](/.appveyor.yml) to create your own.
+We run our tests on Windows agents in AppVeyor. Use our [AppVeyor configuration](/.appveyor.yml) to create your own.