Download the connection script
pgpro-repo-add.sh.
You can also do it using wget:
$ wget --user your-username --ask-password https://repo.postgrespro.ru/ora2pgpro/keys/pgpro-repo-add.sh
Run it with the rights of root.
If your distribution is supported, the repository will be connected.
Note that for a Debian-based system make sure to connect not only
the main section but also
the contrib section since it contains the required
libdbd-oracle-perl package.