Remove Oracle tnsnames rpm repo

Problem to solve

Currently the connection from the CI runners to the OracleDB is hardcoded into a file, any changes to the connection string breaks our CI, see #814 (closed). To solve this problem we have agreed to run the tnsnames rpm on the runner machines and inject the updated file into the containers. Rundeck will take care of configuring the file -> https://gitlab.cern.ch/cta/operations/-/issues/1472

The purpose of this ticket is to remove two, leftover, repo files that have not been used for some time as the installation for the tnsnames were remove from CI months ago.

Stakeholders

• CTA Team