/etc/logcheck/ignore.d.paranoid/ppp is in logcheck-database 1.3.17.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 | ^\w{3} [ :0-9]{11} [._[:alnum:]-]+ pppd\[[0-9]+\]: (sent|rcvd) \[LCP EchoReq id=[[:alnum:]]+ magic=[ [:alnum:]]+\]$
^\w{3} [ :0-9]{11} [._[:alnum:]-]+ pppd\[[0-9]+\]: (sent|rcvd) \[LCP EchoRep id=[[:alnum:]]+ magic=[ [:alnum:]]+\]$
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