[Enterprise Search] Refactor MockRouter test helper to not store payload

[cee-chen]

Summary

1. Past-Constance foolishly assumed we would would only ever have 1 main kind of payload (query, body, or param) to validate
2. Past-Constance also didn't reeeally know how the router worked
3. Present-Constance still doesn't, but has improved our MockRouter helper to no longer take a payload param on MockRouter initialization
4. Instead, when we're validating payloads, we now simply examine the request itself as the payload type(s) are going to be the top-most level keys, e.g.:

{
  query: {
    foo: 'bar',
  },
  body: {
    bar: 'baz',
  }
}

So now Jason no longer needs to create 2 separate routers to test both query and body payloads. Hooray!

Checklist

• Unit or functional tests were updated or added to match the most common scenarios

[scottybollinger]

LGTM. Thanks for doing this!

[cee-chen]

????????????????? WTF is Kibana CI erroring on?

[spalger]

@constancecchen sorry about this, we had a little oopsy and all the in progress PRs died

[cee-chen]

HAHA sorry Spencer, I forgot you are an omnipresent wizard. All good and no worries, I just like yelling at bots because they can't yell back (yet...) 🤖

[scottybollinger]

@constancesearch yell upstream

[cee-chen]

@elasticmachine merge upstream

[cee-chen]

@elasticmachine merge upstream

[cee-chen]

Oh I should actually pay attention to errors someday. Looks like there's new WS tests to updoot

[JasonStoltz]

Constance, thank you so much 100% awesome.

[kibanamachine]

💚 Build Succeeded

• continuous-integration/kibana-ci/pull-request
• Commit: 495fe39

Metrics [docs]

✅ unchanged

History

• 💔 Build #103914 failed 59d289a19290b3e825e1fccc11ff34a4dcd743e5
• 💔 Build #103902 failed 22639b772e8926809b0d09d3163e293898395c6b
• 💚 Build #103536 succeeded 51001c9fec43e1901e83d7716abb86a3b2823feb

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@elasticmachine merge upstream