Fix DeprecationWarning's from elasticsearch-py.

[arnau126]

See https://github.com/elastic/elasticsearch-py/issues/1698 for more information. Fixes #1551 .

[cla-checker-service[bot]]

💚 CLA has been signed

[arnau126]

We can also do something like:

        if elasticsearch.__version__ >= (7, 14, 0):
            key = 'document'
        else:
            key = 'body'
        meta = es.index(
            index=self._get_index(index),
            **{key: self.to_dict(skip_empty=skip_empty)},
            **doc_meta
        )

[arnau126]

@sethmlarson Please, let me know if anything else is required. (I've rebased the branch).

[anze3db]

Could we get a new release with this patch? We are drowning in deprecation warnings 😢

Happy to help if anything else needs to be done before the release, let me know!

[sethmlarson]

Thanks for this, I've created a separate PR which fixed the deprecations for all APIs. The fix is available on v7.4.1 on PyPI.