* develop: (34 commits)
Add a default .m.rule.tombstone push rule (#4867)
Fix infinite loop in presence handler
changelog
more logging improvements
remove extraneous exception logging
Clarify logging when PDU signature checking fails
Changelog
Add --no-pep-517 to README instructions
set PIP_USE_PEP517 = False for tests
Fix handling of SYNAPSE_NO_TLS in docker image (#5005)
Config option for verifying federation certificates (MSC 1711) (#4967)
Remove log error for .well-known/matrix/client (#4972)
Prevent "producer not unregistered" message (#5009)
add gpg key fingerprint
Don't crash on lack of expiry templates
Update debian install docs for new key and repo (#5074)
Add management endpoints for account validity
Send out emails with links to extend an account's validity period
Make sure we're not registering the same 3pid twice
Newsfile
...