/usr/share/postgresql/9.6/ is in postgresql-9.6-pgtap 0.97.0-2.
This file is owned by root:root, with mode 0o755.
..
/usr/share/postgresql/9.6/extension/
/usr/share/postgresql/9.6/extension/pgtap--0.90.0--0.91.0.sql
/usr/share/postgresql/9.6/extension/pgtap--0.91.0--0.92.0.sql
/usr/share/postgresql/9.6/extension/pgtap--0.92.0--0.93.0.sql
/usr/share/postgresql/9.6/extension/pgtap--0.93.0--0.94.0.sql
/usr/share/postgresql/9.6/extension/pgtap--0.94.0--0.95.0.sql
/usr/share/postgresql/9.6/extension/pgtap--0.95.0--0.96.0.sql
/usr/share/postgresql/9.6/extension/pgtap--0.96.0--0.97.0.sql
/usr/share/postgresql/9.6/extension/pgtap--0.97.0.sql
/usr/share/postgresql/9.6/extension/pgtap--unpackaged--0.91.0.sql
/usr/share/postgresql/9.6/extension/pgtap-core--0.97.0.sql
/usr/share/postgresql/9.6/extension/pgtap-schema--0.97.0.sql
/usr/share/postgresql/9.6/extension/pgtap.control