MNT Add GitHub Actions CI

.github/workflows/ci.yml

@@ -0,0 +1,18 @@
+name: CI
+
+on:
+  push:
+  pull_request:
+  workflow_dispatch:
+  # Every Tuesday at 2:20pm UTC
+  schedule:
+    - cron: '20 14 * * 2'
+
+jobs:
+  ci:
+    uses: silverstripe/gha-ci/.github/workflows/ci.yml@v1
+    with:
+      # Turn phpcoverage off because it causes a segfault
+      phpcoverage_force_off: true
+      # There is a strange behat.yml file in framework that runs behat tests in the admin module
+      endtoend: false

.github/workflows/keepalive.yml

@@ -0,0 +1,16 @@
+
+name: Keepalive
+
+on:
+  # The 4th of every month at 10:50am UTC
+  schedule:
+    - cron: '50 10 4 * *'
+  workflow_dispatch:
+
+jobs:
+  keepalive:
+    name: Keepalive
+    runs-on: ubuntu-latest
+    steps:
+      - name: Keepalive
+        uses: silverstripe/gha-keepalive@v1

README.md

@@ -1,6 +1,6 @@
 ## SilverStripe Framework
 
-[![Build Status](https://api.travis-ci.com/silverstripe/silverstripe-framework.svg?branch=4)](https://travis-ci.com/silverstripe/silverstripe-framework)
+[![CI](https://github.com/silverstripe/silverstripe-framework/actions/workflows/ci.yml/badge.svg)](https://github.com/silverstripe/silverstripe-framework/actions/workflows/ci.yml)
 [![Build Docs](https://github.com/silverstripe/silverstripe-framework/workflows/Build%20Docs/badge.svg)](https://docs.silverstripe.org/)
 [![Latest Stable Version](https://poser.pugx.org/silverstripe/framework/version.svg)](https://www.silverstripe.org/stable-download/)
 [![Latest Unstable Version](https://poser.pugx.org/silverstripe/framework/v/unstable.svg)](https://packagist.org/packages/silverstripe/framework)