Bump compileSdk to 31 (#5563)

app/build.gradle.kts

@@ -22,7 +22,6 @@ val SUPPORTED_ABIS = setOf("armeabi-v7a", "arm64-v8a", "x86")
 
 android {
     compileSdkVersion(AndroidConfig.compileSdk)
-    buildToolsVersion(AndroidConfig.buildTools)
     ndkVersion = AndroidConfig.ndk
 
     defaultConfig {

buildSrc/src/main/kotlin/AndroidConfig.kt

@@ -1,7 +1,6 @@
 object AndroidConfig {
-    const val compileSdk = 30
+    const val compileSdk = 31
     const val minSdk = 23
     const val targetSdk = 29
-    const val buildTools = "30.0.3"
     const val ndk = "22.1.7171670"
 }