CI: development builds are now signed with publically-shared key

This commit adds keystore which is shared with community. People freely can
use it for creating own Termux app and plugin builds. However, builds signed
with such keystore cannot be proven as official.

Signed-off-by: Leonid Plyushch <leonid.plyushch@gmail.com>

.cirrus.yml

@@ -4,37 +4,17 @@ container:
   memory: 8G
 
 task:
-  name: Run tests
+  name: tests
   script: ./gradlew test
 
 task:
-  name: Build release apk
+  name: debug-build
 
   depends_on:
-    - Run tests
-
-  environment:
-    KEYSTORE: ENCRYPTED[e3fa3d741db3c2929acabef0c954e995b7f86d8229f7796199ce6e15ae98cb8eae16b2e498b9daeafff35e1f3aba3f8f]
-    KEYSTORE_PASSWORD: ENCRYPTED[2761e799baef14b1c822dfcbe5a40ba3ae8e8c13be25563baed28ff35f66e51fa725aa9dcd29c0698023cd04a8ebd604]
+    - tests
 
   build_release_apk_script: |
-    ./gradlew assembleRelease
+    ./gradlew assembleDebug
 
-  build_apksigner_script: |
-    cd ../
-    git clone https://github.com/fornwall/apksigner
-    cd apksigner
-    ./gradlew
-    cp ./build/libs/apksigner-all.jar /tmp/apksigner.jar
-
-  sign_release_apk_script: |
-    echo "$KEYSTORE" | base64 -d > keystore.jks
-    java -jar /tmp/apksigner.jar -p "$KEYSTORE_PASSWORD" keystore.jks \
-      ./app/build/outputs/apk/release/app-release-unsigned.apk \
-      ./termux-release-g${CIRRUS_CHANGE_IN_REPO:0:8}.apk
-
-  release_artifacts:
-    path: "./*.apk"
-
-  unsigned_artifacts:
-    path: "./app/build/outputs/apk/release/*.apk"
+  output_artifacts:
+    path: "./app/build/outputs/apk/debug/*.apk"