Log Message:
nginx-devel: updated to 1.21.0

Changes with nginx 1.21.0

*) Security: 1-byte memory overwrite might occur during DNS server
   response processing if the "resolver" directive was used, allowing an
   attacker who is able to forge UDP packets from the DNS server to
   cause worker process crash or, potentially, arbitrary code execution
   (CVE-2021-23017).

*) Feature: variables support in the "proxy_ssl_certificate",
   "proxy_ssl_certificate_key" "grpc_ssl_certificate",
   "grpc_ssl_certificate_key", "uwsgi_ssl_certificate", and
   "uwsgi_ssl_certificate_key" directives.

*) Feature: the "max_errors" directive in the mail proxy module.

*) Feature: the mail proxy module supports POP3 and IMAP pipelining.

*) Feature: the "fastopen" parameter of the "listen" \ 
directive in the
   stream module.
   Thanks to Anbang Wen.

*) Bugfix: special characters were not escaped during automatic redirect
   with appended trailing slash.

*) Bugfix: connections with clients in the mail proxy module might be
   closed unexpectedly when using SMTP pipelining.