Handle top level json array

[GrosSacASac]

fixes https://github.com/node-formidable/formidable/issues/760

@Rush have a try

[Rush]

@GrosSacASac gladly but this branch is ESM only so it's no-go :-(

» node index.js
internal/modules/cjs/loader.js:1089
      throw new ERR_REQUIRE_ESM(filename, parentPath, packageJsonPath);
      ^

Error [ERR_REQUIRE_ESM]: Must use import to load ES Module: /code/formidable-test/node_modules/formidable/src/index.js
require() of ES modules is not supported.
require() of /code/formidable-test/node_modules/formidable/src/index.js from /code/formidable-test/index.js is an ES module file as it is a .js file whose nearest parent package.json contains "type": "module" which defines all .js files in that package scope as ES modules.
Instead rename /code/formidable-test/node_modules/formidable/src/index.js to end in .cjs, change the requiring code to use import(), or remove "type": "module" from /code/formidable-test/node_modules/formidable/package.json.

    at Object.Module._extensions..js (internal/modules/cjs/loader.js:1089:13)
    at Module.load (internal/modules/cjs/loader.js:937:32)
    at Function.Module._load (internal/modules/cjs/loader.js:778:12)
    at Module.require (internal/modules/cjs/loader.js:961:19)
    at require (internal/modules/cjs/helpers.js:92:18)
    at Object.<anonymous> (/code/formidable-test/index.js:2:20)
    at Module._compile (internal/modules/cjs/loader.js:1072:14)
    at Object.Module._extensions..js (internal/modules/cjs/loader.js:1101:10)
    at Module.load (internal/modules/cjs/loader.js:937:32)
    at Function.Module._load (internal/modules/cjs/loader.js:778:12) {
  code: 'ERR_REQUIRE_ESM'
}

ESM reminds me of Python 2 to Python 3 migration. A never-ending story with no happy ending :-(

[GrosSacASac]

Make it a yes-go :)

[Rush]

Sorry I didn't have time to test with ESM yet.