switch CI from Travis CI to Github Actions

.github/dependabot.yml

@@ -0,0 +1,8 @@
+# see https://docs.github.com/github/administering-a-repository/configuration-options-for-dependency-updates
+
+version: 2
+updates:
+  - package-ecosystem: "github-actions"
+    directory: "/"
+    schedule:
+      interval: "weekly"

.github/workflows/tests.yml

@@ -0,0 +1,20 @@
+---
+name: Tests
+on:
+  push:
+  pull_request:
+    types: [opened]
+  schedule:
+    - cron: '16 19 24 * *'
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v4
+    - name: run tests
+      run: cd test && ./run-tests.sh
+    - name: shellcheck
+      uses: ludeeus/action-shellcheck@2.0.0
+      with:
+        scandir: '.'

README.md

@@ -1,7 +1,7 @@
 dns-update
 ==========
 
-[![Build Status](https://travis-ci.org/mmitch/dns-update.svg?branch=master)](https://travis-ci.org/mmitch/dns-update)
+[![Build status](https://github.com/mmitch/dns-update/workflows/Tests/badge.svg)](https://github.com/mmitch/dns-update/actions?query=workflow%3ATests)
 [![GPL 3+](https://img.shields.io/badge/license-GPL%203%2B-blue.svg)](http://www.gnu.org/licenses/gpl-3.0-standalone.html)
 
 * dns-update - small dynamic DNS suite using SSH