Setup nighlty build + GitHub action

.github/workflows/nightly.yml

@@ -0,0 +1,25 @@
+name: Build and release nightly APK
+
+on:
+  schedule:
+    # Every nights at 4
+    - cron: "0 4 * * *"
+
+env:
+  GRADLE_OPTS: -Dorg.gradle.jvmargs="-Xmx3072m -Dfile.encoding=UTF-8 -XX:+HeapDumpOnOutOfMemoryError" -Dkotlin.daemon.jvm.options="-Xmx2560m" -Dkotlin.incremental=false
+  CI_GRADLE_ARG_PROPERTIES: --stacktrace -PpreDexEnable=false --max-workers 2 --no-daemon
+
+jobs:
+  nightly:
+    name: Build and publish nightly APK to Firebase
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+      - name: Build and upload Nightly APK
+        run: |
+          ./gradlew assembleNightly appDistributionUploadNightly $CI_GRADLE_ARG_PROPERTIES
+        env:
+          ELEMENT_ANDROID_NIGHTLY_KEYID: ${{ secrets.ELEMENT_ANDROID_NIGHTLY_KEYID }}
+          ELEMENT_ANDROID_NIGHTLY_KEYPASSWORD: ${{ secrets.ELEMENT_ANDROID_NIGHTLY_KEYPASSWORD }}
+          ELEMENT_ANDROID_NIGHTLY_STOREPASSWORD: ${{ secrets.ELEMENT_ANDROID_NIGHTLY_STOREPASSWORD }}
+          FIREBASE_TOKEN: ${{ secrets.ELEMENT_ANDROID_NIGHTLY_FIREBASE_TOKEN }}