Fix in mock_elasticsearch_response_sources

[lafeber]

The "_id" is currently the incrementing id from the each_with_index loop. However, this id is eventually used in the all_scope_where_ids_in method, where it subsequently fails.

If you add id: ... to your hits that are passed as a parameter in the mock_elasticsearch_response_sources method, this helper method now works.

Fixes #862

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• Added tests.
• Added an entry to the changelog if the new code introduces user-observable changes. See changelog entry format for details.

[lafeber]

@konalegi do you have time to look at this?

[konalegi]

GitHub actions are stuck, let me try them run first. Not sure why they are not starting.

[konalegi]

@lafeber could you please rebase your branch with the master?

[konalegi]

Also, please provide a changelog entry, so that will be easier to generate a release (example)

[lafeber]

@konalegi I'm sorry this issue disappeared from my radar. I've updated with master and added a changelog entry.

[konalegi]

@lafeber thanks!