/usr/share/lintian/overrides/nginx-common is in nginx-common 1.9.15-0ubuntu1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 | # /var/www/html is the default document root
nginx-common: dir-or-file-in-var-www var/www/html/
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