Upgrade OS, Python and Sphinx for RTD build Config

Upgrade OS, Python and Sphinx for RTD build Config

- Updated .readthedocs.yaml (build config) to use
	OS: ubuntu-24.04
	Python 3.12 (as this is what Ubunut-24 includes)
- tox.ini basepython to 3 (will use whatever release OS has)
- tox.ini Removed all python dependency constraints as they prevented using newer sphinx version)
- requirement-docs: Sphinx to version 8.2.0 (to work with python 3.12 or higher)
- conf.py add required extension and exclusion patterns for unused files

Issue-ID:CPS-2864
Change-Id: Ieba43ec84f1f1397b1c2bd2358b2dd65e2c7143f
Signed-off-by: ToineSiebelink <toine.siebelink@est.tech>