Merges [38727] to the 4.6 branch.
Fixes#38070, #37733 by reverting part of [38429] and using the fix in Requests.
Fixes#37992 allowing for connecting to SSL resources on ports other than 443.
Fixes#37991 by not sending default ports in the `Host:` header.
Fixes#37839 to match and decode Chunked responses correctly.
Fixes#38232 allowing a SSL connection to ignore the hostname of the certificate when verification is disabled.
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