Allow passing trust_env to aiohttp.ClientSession

[michaeloliverx]

Is your feature request related to a problem?

I want to pass trust_env=True to the aiohttp.ClientSession here:

opensearch-py/opensearchpy/_async/http_aiohttp.py

Lines 356 to 366 in 03b72c3

	self.session = aiohttp.ClientSession(
	headers=self.headers,
	skip_auto_headers=("accept", "accept-encoding"),
	auto_decompress=True,
	loop=self.loop,
	cookie_jar=aiohttp.DummyCookieJar(),
	response_class=OpenSearchClientResponse,
	connector=aiohttp.TCPConnector(
	limit=self._limit, use_dns_cache=True, ssl=self._ssl_context
	),
	)

This will allow allow proxy configuration via HTTPS_PROXY environment variables.
See https://docs.aiohttp.org/en/latest/client_advanced.html?highlight=proxy#proxy-support

What solution would you like?

AsyncOpenSearch to accept the trust_env keyword argument and pass it onto the connection class.

[Temirlan-qa]

@michaeloliverx I have made a PR to solve this issue 372