MNT Use GitHub Actions CI

.github/workflows/ci.yml

@@ -0,0 +1,16 @@
+name: CI
+
+on:
+  push:
+  pull_request:
+  workflow_dispatch:
+  # Every Sunday at 12:10pm UTC
+  schedule:
+    - cron: '10 12 * * 0'
+
+jobs:
+  ci:
+    name: CI
+    # Only run cron on the symbiote account
+    if: (github.event_name == 'schedule' && startsWith(github.repository, 'symbiote/')) || (github.event_name != 'schedule')
+    uses: silverstripe/gha-ci/.github/workflows/ci.yml@v1

.github/workflows/keepalive.yml

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+name: Keepalive
+
+on:
+  workflow_dispatch:
+  # The 7th of every month at 12:50pm UTC
+  schedule:
+    - cron: '50 12 7 * *'
+
+jobs:
+  keepalive:
+    name: Keepalive
+    # Only run cron on the symbiote account
+    if: (github.event_name == 'schedule' && startsWith(github.repository, 'symbiote/')) || (github.event_name != 'schedule')
+    runs-on: ubuntu-latest
+    steps:
+      - name: Keepalive
+        uses: silverstripe/gha-keepalive@v1

README.md

@@ -1,6 +1,6 @@
 # SilverStripe Grid Field Extensions Module
 
-[![Build Status](https://travis-ci.org/symbiote/silverstripe-gridfieldextensions.svg?branch=master)](https://travis-ci.org/symbiote/silverstripe-gridfieldextensions)
+[![CI](https://github.com/symbiote/silverstripe-gridfieldextensions/actions/workflows/ci.yml/badge.svg)](https://github.com/symbiote/silverstripe-gridfieldextensions/actions/workflows/ci.yml)
 [![SilverStripe supported module](https://img.shields.io/badge/silverstripe-supported-0071C4.svg)](https://www.silverstripe.org/software/addons/silverstripe-commercially-supported-module-list/)
 [![Latest Stable Version](https://poser.pugx.org/symbiote/silverstripe-gridfieldextensions/version.svg)](https://github.com/symbiote/silverstripe-gridfieldextensions/releases)
 [![Latest Unstable Version](https://poser.pugx.org/symbiote/silverstripe-gridfieldextensions/v/unstable.svg)](https://packagist.org/packages/symbiote/silverstripe-gridfieldextensions)