[client] Add release signing key

client/android/app/build.gradle

@@ -5,6 +5,13 @@ plugins {
     id "dev.flutter.flutter-gradle-plugin"
 }
 
+
+def releaseProperties = new Properties()
+def releasePropertiesFile = rootProject.file('keystore-release.properties')
+if (releasePropertiesFile.exists()) {
+    releaseProperties.load(new FileInputStream(releasePropertiesFile))
+}
+
 android {
     namespace = "cloud.phylum.drive"
     compileSdk = flutter.compileSdkVersion
@@ -26,16 +33,24 @@ android {
         versionCode = flutter.versionCode
         versionName = flutter.versionName
 
+
         ndk {
             abiFilters 'armeabi-v7a', 'arm64-v8a', 'x86_64'
         }
     }
 
+    signingConfigs {
+        release {
+            keyAlias releaseProperties['keyAlias']
+            keyPassword releaseProperties['keyPassword']
+            storeFile rootProject.file(releaseProperties['storeFile'])
+            storePassword releaseProperties['storePassword']
+        }
+    }
+
     buildTypes {
         release {
-            // TODO: Add your own signing config for the release build.
-            // Signing with the debug keys for now, so `flutter run --release` works.
-            signingConfig = signingConfigs.debug
+            signingConfig = signingConfigs.release
         }
     }
 }