Issue Description

I'm looking at this line and I think it's a problem when I have the following data for source and target:

// New data
source: []

// Previous data
target: [{...}]

My expectation is that the data will be replaced with source, which is the most recent data. But in this case, because Object.keys([]) returns an empty array, it will returns target instead.

Link to Reproduction

n/a

Reproduction Steps

No response

@apollo/client version

3.9.5