Upgrade billing / cleanup

app/build.gradle

@@ -7,7 +7,6 @@ apply plugin: 'com.google.gms.google-services' // Crashlytics
 apply plugin: 'com.google.firebase.crashlytics'
 
 repositories {
-    maven { url 'https://maven.fabric.io/public' }
     maven { url 'https://jitpack.io' } // required for MPAndroidChart
     jcenter() // for kotlin serialization
 }
@@ -117,7 +116,7 @@ dependencies {
     implementation 'com.google.android.libraries.places:places:2.3.0'
 
     // Billing / Subscriptions
-    implementation 'com.android.billingclient:billing:3.0.0'
+    implementation 'com.android.billingclient:billing:3.0.1'
 
     // Firebase
     implementation 'com.google.firebase:firebase-core:17.5.0'