v1.1.7

What's Changed

• Security: Fix a possible injection vulnerability (a variant of
  https://consensys.net/diligence/vulnerabilities/python-smtplib-multiple-crlf-injection/)

  Note that in order to exploit this vulnerability in aiosmtplib, the attacker would need
  control of the hostname or source_address parameters. Thanks Sam Sanoop @ Snyk
  for bringing this to my attention.

• Bugfix: include CHANGLOG in sdist release

• Type hints: fix type hints for async context exit (credit @JelleZijlstra)
  Full Changelog: v1.1.6...v1.1.7