async function decompress(filePath, cacheDir) {
  if (filePath.endsWith('.zip')) {
    await unzip(filePath, cacheDir);
  } else {
    await tar.extract({
      file: filePath,
      C: cacheDir
    });
  }
}
Decompresses a file at `filePath` to `cacheDir` directory.
@param {string} filePath  - file path to compressed binary
@param {string} cacheDir  - directory to decompress into