config rebuild: keep defaultPass

[paulirish]

example config:

module.exports = {
  "extends": "lighthouse:default",
  "settings": {
    "onlyAudits": [
      "is-on-https"
    ]
  }
}

This ends up filtering out the defaultPass as there are no audits consuming a trace from it.
There are other ways to fix this.
This is but one.

[patrickhulce]

I'm still partial to checking if they requested the devtoolsLog artifact for keeping it, but that only applies to like 2 audits so I'm cool with this too

[brendankenny]

I'm still partial to checking if they requested the devtoolsLog artifact for keeping it

yeah, that would have gotten us closer to where we need to be wrt to ditching defaultPass.

Also needs a test :P