Pin Android r8 version until we're on AGP 8.2

settings.gradle

@@ -1,4 +1,16 @@
 pluginManagement {
+    buildscript {
+        repositories {
+            mavenCentral()
+            maven { url = uri("https://storage.googleapis.com/r8-releases/raw") }
+        }
+        dependencies {
+            // https://issuetracker.google.com/issues/227160052#comment37
+            // This can be removed when we switch to Android Gradle plugin 8.2.
+            classpath("com.android.tools:r8:8.2.28")
+        }
+    }
+
     repositories {
         gradlePluginPortal()
         google()