Add Github Actions workflows (#4)

This commit adds Github Actions workflows for building the XR
Fundamentals codelab. The workflows are defined in the
following files:

- .github/workflows/xr-fundamentals-part1-build-app.yml
- .github/workflows/xr-fundamentals-part2-build-app.yml
- .github/workflows/xr-fundamentals-start-build-app.yml

These workflows will be triggered on push and pull request
events to the main branch. They can also trigger manually
with `workflow_dispatch`. They will build the app for each
part of the codelab.

Author: cartland

.github/workflows/xr-fundamentals-part1-build-app.yml

@@ -0,0 +1,33 @@
+# Workflow name
+name: Build XR Fundamentals Codelab - Part 1
+
+on:
+  workflow_dispatch:
+  push:
+    branches: [ main ]
+  pull_request:
+    branches: [ main ]
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+
+      - name: Set Up JDK
+        uses: actions/setup-java@v3
+        with:
+          distribution: 'zulu'
+          java-version: '17'
+          cache: 'gradle'
+
+      - name: Setup Gradle
+        uses: gradle/actions/setup-gradle@v4
+
+      - name: Make gradlew executable
+        run: chmod +x ./gradlew
+        working-directory: ./xr-codelabs/xr-fundamentals/part1
+
+      - name: Build app
+        working-directory: ./xr-codelabs/xr-fundamentals/part1
+        run: ./gradlew :app:assembleDebug

.github/workflows/xr-fundamentals-part2-build-app.yml

@@ -0,0 +1,33 @@
+# Workflow name
+name: Build XR Fundamentals Codelab - Part 2
+
+on:
+  workflow_dispatch:
+  push:
+    branches: [ main ]
+  pull_request:
+    branches: [ main ]
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+
+      - name: Set Up JDK
+        uses: actions/setup-java@v3
+        with:
+          distribution: 'zulu'
+          java-version: '17'
+          cache: 'gradle'
+
+      - name: Setup Gradle
+        uses: gradle/actions/setup-gradle@v4
+
+      - name: Make gradlew executable
+        run: chmod +x ./gradlew
+        working-directory: ./xr-codelabs/xr-fundamentals/part2
+
+      - name: Build app
+        working-directory: ./xr-codelabs/xr-fundamentals/part2
+        run: ./gradlew :app:assembleDebug

.github/workflows/xr-fundamentals-start-build-app.yml

@@ -0,0 +1,33 @@
+# Workflow name
+name: Build XR Fundamentals Codelab - Start
+
+on:
+  workflow_dispatch:
+  push:
+    branches: [ main ]
+  pull_request:
+    branches: [ main ]
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+
+      - name: Set Up JDK
+        uses: actions/setup-java@v3
+        with:
+          distribution: 'zulu'
+          java-version: '17'
+          cache: 'gradle'
+
+      - name: Setup Gradle
+        uses: gradle/actions/setup-gradle@v4
+
+      - name: Make gradlew executable
+        run: chmod +x ./gradlew
+        working-directory: ./xr-codelabs/xr-fundamentals/start
+
+      - name: Build app
+        working-directory: ./xr-codelabs/xr-fundamentals/start
+        run: ./gradlew :app:assembleDebug