ci: Migrate from circleci to GH actions (#42)

.github/workflows/ci.yml

@@ -0,0 +1,26 @@
+name: Build
+on:
+  push:
+    branches: [ main ]
+    paths-ignore:
+      - '**.md' # Do not need to run CI for markdown changes.
+  pull_request:
+    branches: [ main ]
+    paths-ignore:
+      - '**.md'
+
+jobs:
+  macos-build:
+    runs-on: macos-13
+
+    steps:
+      - uses: actions/checkout@v4
+        with:
+          fetch-depth: 0 # If you only need the current version keep this.
+
+      - uses: maxim-lobanov/setup-xcode@60606e260d2fc5762a71e64e74b2174e8ea3c8bd
+        with:
+          xcode-version: 15.0.1
+
+      - name: Build hello-macos
+        run: xcodebuild build -scheme 'hello-macos' | xcpretty

README.md

@@ -1,6 +1,11 @@
 ### LaunchDarkly Sample macOS Application ###
+
+[![Build](https://github.com/launchdarkly/hello-macos/actions/workflows/ci.yml/badge.svg)](https://github.com/launchdarkly/hello-macos/actions/workflows/ci.yml)
+
 We've built a simple macOS application that demonstrates how LaunchDarkly's SDK works. Below, you'll find the basic build procedure, but for more comprehensive instructions, you can visit your [Quickstart page](https://app.launchdarkly.com/quickstart#/).
+
 ##### Build instructions #####
+
 1. Make sure you have [XCode](https://itunes.apple.com/us/app/xcode/id497799835?ls=1&mt=12) installed
 2. Open `hello-macos.xcworkspace` in XCode
 3. Copy the mobile key from your account settings page and the feature flag key from your LaunchDarkly dashboard into `AppDelegate.swift`