Rename es to client in examples for consistency

[iuliaferoli]

Changed examples / docs to only refer to the client instance as client rather than es so we now have uniform naming conventions for clarity.

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[pquentin]

Great work, thanks!

git grep "\bes\b" | grep -v '{es}' | grep -v '^test_elasticsearch' gave three more places to update:

• elasticsearch-py/elasticsearch/helpers/actions.py

  Lines 659 to 663 in 66798fd

  	scan(es,
  	query={"query": {"match": {"title": "python"}}},
  	index="orders-*",
  	doc_type="books"
  	)

• elasticsearch-py/elasticsearch/_async/helpers.py

  Lines 395 to 402 in 66798fd

  	.. code-block:: python
  	async_scan(
  	es,
  	query={"query": {"match": {"title": "python"}}},
  	index="orders-*"
  	)
  	"""

• elasticsearch-py/docs/guide/connecting.asciidoc

  Lines 251 to 272 in 66798fd

  	from elasticsearch import Elasticsearch
  	# Authenticate from the constructor
  	es = Elasticsearch(
  	"https://localhost:9200",
  	ca_certs="/path/to/http_ca.crt",
  	basic_auth=("username", "password")
  	)
  	# Authenticate via the .options() method:
  	es.options(
  	basic_auth=("username", "password")
  	).indices.get(index="*")
  	# You can persist the authenticated client to use
  	# later or use for multiple API calls:
  	auth_client = es.options(api_key="api_key")
  	for i in range(10):
  	auth_client.index(
  	index="example-index",
  	document={"field": i}
  	)

[pquentin]

I don't want to encourage Cloud IDs which don't really have an advantage over simple endpoints:

Suggested change

	client = Elasticsearch(cloud_id="YOUR_CLOUD_ID", api_key="YOUR_API_KEY")
	client = Elasticsearch("http://localhost:9200/", api_key="YOUR_API_KEY")

[iuliaferoli]

added those three and made the change you suggested, thanks!