Introduce Actions workflow to test without building (#20)

This should prevent the class of issue that happened after #16 was merged, which broke the Action externally.

.github/shared/functional-tests/action.yml

@@ -0,0 +1,40 @@
+name: "Functional tests"
+description: "Run functional tests against the app in lib/index.js"
+
+runs:
+  using: "composite"
+  steps:
+    - name: Load test key
+      shell: bash
+      id: get_key
+      run: |
+        value=$(cat src/tests/test_key_b64.txt)
+        echo "text=$value" >> $GITHUB_OUTPUT
+
+    - uses: ./
+      name: zipalign and Sign APK
+      with:
+        releaseDirectory: src/tests/apk-zip
+        signingKeyBase64: ${{ steps.get_key.outputs.text }}
+        alias: test_key
+        keyStorePassword: android
+        keyPassword: android
+        zipAlign: true
+
+    - uses: ./
+      name: Sign APK
+      with:
+        releaseDirectory: src/tests/apk
+        signingKeyBase64: ${{ steps.get_key.outputs.text }}
+        alias: test_key
+        keyStorePassword: android
+        keyPassword: android
+
+    - uses: ./
+      name: Sign AAB
+      with:
+        releaseDirectory: src/tests/aab
+        signingKeyBase64: ${{ steps.get_key.outputs.text }}
+        alias: test_key
+        keyStorePassword: android
+        keyPassword: android

.github/workflows/build-and-test.yml

@@ -0,0 +1,42 @@
+name: "Build and test"
+
+on:
+  push:
+    branches:
+      - main
+  pull_request:
+    branches:
+      - main
+  workflow_dispatch:
+
+jobs:
+  build-and-test:
+    runs-on: ubuntu-latest
+    name: Build and test
+
+    steps:
+      - uses: actions/checkout@v4
+        name: Checkout
+
+      - name: Install dependencies
+        run: npm install
+
+      - name: Build
+        run: npm run build
+
+      - name: eslint
+        run: npx eslint
+
+      - name: Ensure no pending Git changes
+        run: |
+          GIT_STATUS=$(git status --porcelain)
+          if [[ -n $GIT_STATUS ]]; then
+            echo "There are pending Git changes after running the build. Did you forget to commit the .js files?"
+            echo "$GIT_STATUS"
+            exit 1
+          fi
+
+      - name: Run unit tests
+        run: npm run test
+
+      - uses: "./.github/shared/functional-tests"

.github/workflows/test-no-build.yml

@@ -0,0 +1,18 @@
+name: "Test compiled action"
+
+on:
+  push:
+    branches:
+      - main
+  workflow_dispatch:
+
+jobs:
+  test:
+    runs-on: ubuntu-latest
+    name: Test action
+
+    steps:
+      - uses: actions/checkout@v4
+        name: Checkout
+
+      - uses: "./.github/shared/functional-tests"