/usr/share/postgresql/10/extension/ is in postgresql-10-partman 3.1.2-1.
This file is owned by root:root, with mode 0o755.
..
/usr/share/postgresql/10/extension/pg_partman--0.1.0--0.1.1.sql
/usr/share/postgresql/10/extension/pg_partman--0.1.1--0.1.2.sql
/usr/share/postgresql/10/extension/pg_partman--0.1.2--0.2.0.sql
/usr/share/postgresql/10/extension/pg_partman--0.2.0--0.3.0.sql
/usr/share/postgresql/10/extension/pg_partman--0.3.0--0.3.1.sql
/usr/share/postgresql/10/extension/pg_partman--0.3.1--0.3.2.sql
/usr/share/postgresql/10/extension/pg_partman--0.3.2--0.4.0.sql
/usr/share/postgresql/10/extension/pg_partman--0.4.0--0.4.1.sql
/usr/share/postgresql/10/extension/pg_partman--0.4.1--0.4.2.sql
/usr/share/postgresql/10/extension/pg_partman--0.4.2--1.0.0.sql
/usr/share/postgresql/10/extension/pg_partman--1.0.0--1.1.0.sql
/usr/share/postgresql/10/extension/pg_partman--1.1.0--1.2.0.sql
/usr/share/postgresql/10/extension/pg_partman--1.2.0--1.3.0.sql
/usr/share/postgresql/10/extension/pg_partman--1.3.0--1.4.0.sql
/usr/share/postgresql/10/extension/pg_partman--1.4.0--1.4.1.sql
/usr/share/postgresql/10/extension/pg_partman--1.4.1--1.4.2.sql
/usr/share/postgresql/10/extension/pg_partman--1.4.2--1.4.3.sql
/usr/share/postgresql/10/extension/pg_partman--1.4.3--1.4.4.sql
/usr/share/postgresql/10/extension/pg_partman--1.4.4--1.4.5.sql
/usr/share/postgresql/10/extension/pg_partman--1.4.5--1.5.0.sql
/usr/share/postgresql/10/extension/pg_partman--1.5.0--1.5.1.sql
/usr/share/postgresql/10/extension/pg_partman--1.5.1--1.6.0.sql
/usr/share/postgresql/10/extension/pg_partman--1.6.0--1.6.1.sql
/usr/share/postgresql/10/extension/pg_partman--1.6.1--1.7.0.sql
/usr/share/postgresql/10/extension/pg_partman--1.7.0--1.7.1.sql
/usr/share/postgresql/10/extension/pg_partman--1.7.1--1.7.2.sql
/usr/share/postgresql/10/extension/pg_partman--1.7.2--1.8.0.sql
/usr/share/postgresql/10/extension/pg_partman--1.8.0--1.8.1.sql
/usr/share/postgresql/10/extension/pg_partman--1.8.1--1.8.2.sql
/usr/share/postgresql/10/extension/pg_partman--1.8.2--1.8.3.sql
/usr/share/postgresql/10/extension/pg_partman--1.8.3--1.8.4.sql
/usr/share/postgresql/10/extension/pg_partman--1.8.4--1.8.5.sql
/usr/share/postgresql/10/extension/pg_partman--1.8.5--1.8.6.sql
/usr/share/postgresql/10/extension/pg_partman--1.8.6--1.8.7.sql
/usr/share/postgresql/10/extension/pg_partman--1.8.7--1.8.8.sql
/usr/share/postgresql/10/extension/pg_partman--1.8.7--2.0.0.sql
/usr/share/postgresql/10/extension/pg_partman--1.8.8--2.0.0.sql
/usr/share/postgresql/10/extension/pg_partman--2.0.0--2.1.0.sql
/usr/share/postgresql/10/extension/pg_partman--2.1.0--2.2.0.sql
/usr/share/postgresql/10/extension/pg_partman--2.2.0--2.2.1.sql
/usr/share/postgresql/10/extension/pg_partman--2.2.1--2.2.2.sql
/usr/share/postgresql/10/extension/pg_partman--2.2.2--2.2.3.sql
/usr/share/postgresql/10/extension/pg_partman--2.2.3--2.3.0.sql
/usr/share/postgresql/10/extension/pg_partman--2.3.0--2.3.1.sql
/usr/share/postgresql/10/extension/pg_partman--2.3.1--2.3.2.sql
/usr/share/postgresql/10/extension/pg_partman--2.3.2--2.3.3.sql
/usr/share/postgresql/10/extension/pg_partman--2.3.3--2.3.4.sql
/usr/share/postgresql/10/extension/pg_partman--2.3.4--2.4.0.sql
/usr/share/postgresql/10/extension/pg_partman--2.4.0--2.4.1.sql
/usr/share/postgresql/10/extension/pg_partman--2.4.1--2.5.0.sql
/usr/share/postgresql/10/extension/pg_partman--2.5.0--2.5.1.sql
/usr/share/postgresql/10/extension/pg_partman--2.5.1--2.6.0.sql
/usr/share/postgresql/10/extension/pg_partman--2.6.0--2.6.1.sql
/usr/share/postgresql/10/extension/pg_partman--2.6.1--2.6.2.sql
/usr/share/postgresql/10/extension/pg_partman--2.6.2--2.6.3.sql
/usr/share/postgresql/10/extension/pg_partman--2.6.3--2.6.4.sql
/usr/share/postgresql/10/extension/pg_partman--2.6.4--3.0.0.sql
/usr/share/postgresql/10/extension/pg_partman--3.0.0--3.0.1.sql
/usr/share/postgresql/10/extension/pg_partman--3.0.1--3.0.2.sql
/usr/share/postgresql/10/extension/pg_partman--3.0.2--3.1.0.sql
/usr/share/postgresql/10/extension/pg_partman--3.1.0--3.1.1.sql
/usr/share/postgresql/10/extension/pg_partman--3.1.1--3.1.2.sql
/usr/share/postgresql/10/extension/pg_partman--3.1.2.sql
/usr/share/postgresql/10/extension/pg_partman.control