Api Effect: Don't validate when there are no results

[KlapTrap]

Fixes #2682

Although this fixes the issue I think there may be issues within the validation.

@richard-cox why does the validation, when given an empty array for an entity list, not fill out the page of the pagination?

Example

Api Response

{
...
resources: []
total_pages: 1,
total_results: 1
}

What ends up in the store pagination section:

{
...
ids: {}
...
}

Expected:

{
...
ids: { 1: [] }
...
}

[cfdreddbot]

Hey KlapTrap!

Thanks for submitting this pull request! I'm here to inform the recipients of the pull request that you and the commit authors have already signed the CLA.

[KlapTrap]

Created #2684 to track the issue.

[richard-cox]

Created #2685, that should cover validation cases via both the api effect and entity/pagination services