make install fails

[joelonsql]

Hi David,

Thanks for making pgbounder_wrapper.

I'm getting a strange error upon make install.

Below is the full log:

$ lsb_release -a
No LSB modules are available.
Distributor ID:	Ubuntu
Description:	Ubuntu 20.04.2 LTS
Release:	20.04
Codename:	focal

$ psql --version
psql (PostgreSQL) 13.2 (Ubuntu 13.2-1.pgdg20.04+1)

$ make
cp sql/pgbouncer_wrapper.sql sql/pgbouncer_wrapper--1.2.0.sql

$ sudo make install
/bin/mkdir -p '/usr/share/postgresql/13/extension'
/bin/mkdir -p '/usr/share/postgresql/13/extension'
/bin/mkdir -p '/usr/share/doc/postgresql-doc-13/extension'
/usr/bin/install -c -m 644 .//pgbouncer_wrapper.control '/usr/share/postgresql/13/extension/'
/usr/bin/install -c -m 644 .//sql/pgbouncer_wrapper--1.2.0.sql .//sql/pgbouncer_wrapper--1.2.0.sql  '/usr/share/postgresql/13/extension/'
/usr/bin/install: will not overwrite just-created '/usr/share/postgresql/13/extension/pgbouncer_wrapper--1.2.0.sql' with './/sql/pgbouncer_wrapper--1.2.0.sql'
make: *** [/usr/lib/postgresql/13/lib/pgxs/src/makefiles/pgxs.mk:233: install] Error 1