chore: refactor utils (#9053)

This PR

- renames the `utils` folder to `tools` (follows internal practice),
- migrates the contents of `scripts` into `tools` and removes scripts.

tools/remove_version_suffix.js

@@ -0,0 +1,26 @@
+/**
+ * Copyright 2020 Google Inc. All rights reserved.
+ *
+ * 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
+ *
+ *     https://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.
+ */
+
+const fs = require('fs');
+const json = fs.readFileSync('./package.json', 'utf8').toString();
+const pkg = JSON.parse(json);
+const oldVersion = pkg.version;
+const version = oldVersion.replace(/-post$/, '');
+const updated = json.replace(
+  `"version": "${oldVersion}"`,
+  `"version": "${version}"`
+);
+fs.writeFileSync('./package.json', updated);