Fix improper syntax with spread operator

[mongodben]

currently the example shows incorrect JS syntax wherein an object is included within an object.

this change fixes by using the spread operator ....

it might be clearer to the user to not include deleteDog as a variable, but rather just put it directly into the mock results.

Checklist:

• If this PR is a new feature, please reference an issue where a consensus about the design was reached (not necessary for small changes)
• Make sure all of the significant new logic is covered by tests

[apollo-cla]

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[jpvajda]

Thanks for this contribution, I'm going to confirm with @benjamn @brainkim @hwillson if this change should be merged.

[hwillson]

Thanks for catching this @mongodben (and thanks for the ping @jpvajda). I have a feeling the intent here was to just use

{
  result: { data: deleteDog },
}

That might be the cleanest quick change, so we don't have people thinking the spread is necessary for some reason.