[FTR - esArchiver] Update saved_object_api_integration archive to N…

…OT delete SO indices (#161852)

## Summary

Part of #161882

Updates the
`x-pack/test/saved_object_api_integration/common/fixtures/es_archiver/saved_objects/spaces`
archive:
* deleting `mappings.json`
* updating documents in `data.json`

This way, _esArchiver_ will not delete SO indices and recreate them,
eliminating the odds of the related tests being flaky.

CC @jeramysoucy @dmlemeshko