/usr/share/lintian/overrides/libgail-3-0 is in libgail-3-0 3.22.30-1ubuntu1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 | # Historical weirdness, not going to be changed now
libgail-3-0: package-name-doesnt-match-sonames libgailutil-3-0
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