Enable nullish coalescing by default in @babel/parser

[layershifter]

Q	A
Fixed Issues?	Fixes #10813
Patch: Bug Fix?	N
Major: Breaking Change?	N
Minor: New Feature?	Y
Tests Added + Pass?	Y
Documentation PR Link
Any Dependency Changes?
License	MIT

[layershifter]

Hey folks, do you have any ideas why CI fails on this test? 🤔

 FAIL  packages/babel-preset-env/test/targets-parser.spec.js
  ● getTargets › allows 'defaults' query

    expect(received).toEqual(expected) // deep equality

    - Expected
    + Received

      Object {
    -   "android": "77.0.0",
    +   "android": "76.0.0",
        "chrome": "49.0.0",
        "edge": "17.0.0",
        "firefox": "68.0.0",
        "ie": "11.0.0",
        "ios": "12.2.0",
    -   "opera": "63.0.0",
    +   "opera": "46.0.0",
        "safari": "5.1.0",
        "samsung": "9.2.0",
      }

---

babel/packages/babel-preset-env/src/targets-parser.js

Lines 216 to 219 in c9a6898

	const browsers = browserslist(browsersquery, {
	path: options.configPath,
	mobileToDesktop: true,
	});

If I will set mobileToDesktop: false, it passes. I have the same issue on master and it looks that there is a collision in browserNameMap:

  op_mob: "opera",
  opera: "opera",

But I don't understand how it's related to my changes 🤔

[JLHwung]

@layershifter The CI error is unrelated to your changes, it comes from recent browserslist 4.8.1 update, I will fix it in another PR.