[DRE-maint] Bug#954419: OpenSSL EOF handling, severity import

[Sebastian Andrzej Siewior]

Control: severity -1 important

OpenSSL 1.1.1f is in unstable now which reverts the unexpected EOF
reporting via SSL_ERROR_SSL.
In the OpenSSL 3.0 release it will be reported again as SSL_ERROR_SSL
with reason code SSL_R_UNEXPECTED_EOF_WHILE_READING.
Therefore the severity is downgraded to `important' because it no longer
leads to an error during build but will later.

Sebastian