[CMake] Add flag to enable the use of a local directory for external projects#5511

fredroy merged 1 commit intosofa-framework:mastersofa-framework/sofa:masterfrom

bakpaul:25_05_add_mechanism_to_specify_local_folder_for_external_dirbakpaul/sofa:25_05_add_mechanism_to_specify_local_folder_for_external_dirCopy head branch name to clipboard