Provide a way to disable thick-mode during build/install

1. Describe your new request in detail

Thank you for your efforts to provide an Oracle driver for Python that does not need the Oracle client libraries in order to connect to the database!

As you may be aware, software in the main section of the Debian archive must comply with the Debian Free Software Guidelines both itself and any build/run dependencies; thus, we have had odpic & cx_Oracle in the contrib archive section due to the runtime need for the proprietary Oracle client libraries.

With the release of python-oracledb and the availability of the thin-mode driver, I have taken the opportunity to package it for the main section of the archive, as the Oracle client libs are no longer necessary. However, in order to do so successfully, I needed to disable the thick-mode driver -- which I did in a bit of a rough way (patch).

It would be great if there were a supported way to configure/build/deploy only the thin-mode driver and have python-oracledb fail gracefully with a polite error message if the thick-mode driver is requested.

2. Give supporting information about tools and operating systems. Give relevant product version numbers

Debian GNU/Linux testing/unstable
Python 3.11.1
Oracle Database 19.13.0.0.0
python-oracledb 1.2.1

Start by reviewing debian/patches/do_not_build_thick_mode_driver.patch and the build/install configuration it changes. Check how python-oracledb packages the thin- and thick-mode drivers for Debian. Done means a supported thin-only build or deployment option exists, with a polite error when thick mode is requested.