remove unused build.gradle

android/source/build.gradle

-/*
- * Copyright 2019 Google Inc.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *      http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-// Top-level build file where you can add configuration options common to all sub-projects/modules.
-
-// buildscript {
-//
-//     repositories {
-//         google()
-//         jcenter()
-//     }
-//     dependencies {
-//         classpath 'com.android.tools.build:gradle:4.1.3'
-//
-//         // NOTE: Do not place your application dependencies here; they belong
-//         // in the individual module build.gradle files
-//     }
-// }
-//
-// allprojects {
-//     repositories {
-//         google()
-//         jcenter()
-//     }
-// }
-//
-// task clean(type: Delete) {
-//     delete rootProject.buildDir
-// }