[dev-manual] - review contribution section of development

Need to review : https://fusiondirectory-developer-documentation.readthedocs.io/en/dev/fusiondirectory/development/contribute/guidelines.html#

Some elements update or to be deleted due to redundancy.

changed due date to February 28, 2025

added dev-manual label

assigned to @tdockx

added PJ2003-0343 label

changed milestone to %FusionDirectory 1.5

added won't fix label

Nothing seems redundant at first sight.

closed