cli-flags snapshots fail depending on how you run them

[brendankenny]

yarn unit-cli causes a bunch of snapshot errors from #13596 like

  ● CLI flags › screenEmulation › disabled › parses the flag with no value as true

    expect(received).toMatchSnapshot()

    Snapshot name: `CLI flags screenEmulation disabled parses the flag with no value as true 1`

    - Snapshot  - 1
    + Received  + 1

    @@ -1,7 +1,7 @@
      Object {
    -   "$0": "node_modules/jest/bin/jest.js",
    +   "$0": "node_modules/jest-worker/build/workers/processChild.js",
        "_": Array [
          "http://www.example.com",
        ],
        "channel": "cli",
        "chrome-flags": "",

I assume that line can be ignored as well