bpo-37463: match_hostname requires quad-dotted IPv4 (GH-14499)

bpo-37463: match_hostname requires quad-dotted IPv4 (GH-14499)

ssl.match_hostname() no longer accepts IPv4 addresses with additional text
after the address and only quad-dotted notation without trailing
whitespaces. Some inet_aton() implementations ignore whitespace and all data
after whitespace, e.g. '127.0.0.1 whatever'.

Short notations like '127.1' for '127.0.0.1' were already filtered out.

The bug was initially found by Dominik Czarnota and reported by Paul Kehrer.

Signed-off-by: Christian Heimes <christian@python.org>
https://bugs.python.org/issue37463
(cherry picked from commit 477b1b25768945621d466a8b3f0739297a842439)

Co-authored-by: Christian Heimes <christian@python.org>