[skip ci] Remove useless files and solve AGP warnings (#1575)

* chore: Remove useless files

* [skip ci] refactor: Solve deprecation warnings from AGP

buildSrc/src/main/kotlin/AndroidConfig.kt

@@ -2,4 +2,5 @@ object AndroidConfig {
     const val compileSdk = 32
     const val minSdk = 21
     const val targetSdk = 32
+    const val namespace = "eu.kanade.tachiyomi.animeextension"
 }