`verify=False` not work with python bug PHA

[yywing]

Describe the bug

python has ssl bug: https://bugs.python.org/issue37428

This commit try fix it: https://github.com/boto/botocore/commit/e97f5cbb08c509931731b2ec198869f2c0991e97

but create_urllib3_context has default args and context.post_handshake_auth is always True.

Expected Behavior

verfity=False not validate cert.

Current Behavior

When ? (3.6 or smaller )< python version < 3.7.4 and openssl > 1.1.1, then always verfity ssl cert.

Reproduction Steps

--

Possible Solution

https://github.com/boto/botocore/pull/2703

Additional Information/Context

No response

SDK version used

= this commit (https://github.com/boto/botocore/commit/e97f5cbb08c509931731b2ec198869f2c0991e)

Environment details (OS name and version, etc.)

• (3.6 or smaller )< python version < 3.7.4 (suuport PHA)
• openssl > 1.1.1 (support PHA)
• server support tls1.3