Remove defunct proguard rules

app/build.gradle.kts

@@ -107,7 +107,6 @@ android {
     productFlavors {
         create("generic") {
             setDimension("store")
-            proguardFile("generic.pro")
         }
         create("googleplay") {
             setDimension("store")

app/generic.pro

@@ -1 +0,0 @@
--dontwarn com.google.api.client.googleapis.extensions.android.gms.auth.*

app/proguard.pro

@@ -9,14 +9,6 @@
     public static *** i(...);
 }
 
-# https://code.google.com/p/android/issues/detail?id=78293
--keep public class android.support.v7.widget.** { *; }
--keep public class android.support.v7.internal.widget.** { *; }
--keep public class android.support.v7.internal.view.menu.** { *; }
--keep public class * extends android.support.v4.view.ActionProvider {
-    public <init>(android.content.Context);
-}
-
 # google-rfc-2445-20110304
 -dontwarn com.google.ical.compat.jodatime.**