Regression in git send-email parsing sendemail.* config values

I recently noticed that git send-email was attempting to send emails using the wrong email address. I have a global email configuration in XDG_CONFIG_HOME, and a specific one set in the {repo}/.git/config of some repos... this was trying to use the global configuration.

`git config -l | grep ^sendemail.smtpserver=` reports two emails

`git config --get sendemail.smtpserver` reports only the second, repo-specific one

I bisected the issue to commit c95e3a3f0b8107b5dc7eac9dfdb9e5238280c9fb

    send-email: move trivial config handling to Perl

Using this commit, git-send-email disagrees with git config --get on which email to use.

Using commit f4dc9432fd287bde9100488943baf3c6a04d90d1 immediately preceding this commit, git send-email agrees with git config --get.