/usr/share/lintian/overrides/xfce4-panel is in xfce4-panel 4.11.0-0ubuntu1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 | #Panel includes its library
xfce4-panel: package-name-doesnt-match-sonames libxfce4panel-1.0-4 libxfce4panel-2.0-4
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