build: use Android API 29

Change-Id: I77b40911c9f0b2f620d6a730b7087b37f7b90615

docker/Dockerfile

@@ -49,8 +49,8 @@ RUN (while sleep 1; do echo "y"; done) | sdkmanager --update
 
 # Android SDK libraries, NDK
 ENV ANDROID_DEPS=\
-'build-tools;28.0.3 \
- platforms;android-28 \
+'build-tools;29.0.0 \
+ platforms;android-29 \
  extras;android;m2repository \
  extras;google;m2repository \
  ndk;20.0.5594570'

ring-android/app/build.gradle

@@ -3,11 +3,11 @@ apply plugin: 'com.android.application'
 def buildFirebase = project.hasProperty('buildFirebase') || getGradle().getStartParameter().getTaskRequests().toString().contains('Firebase')
 
 android {
-    compileSdkVersion 28
-    buildToolsVersion '28.0.3'
+    compileSdkVersion 29
+    buildToolsVersion '29.0.0'
     defaultConfig {
         minSdkVersion 21
-        targetSdkVersion 28
+        targetSdkVersion 29
         versionCode 170
         versionName "20190607-01"
     }