remove empty strings from FetchContent to eliminate cmake build warnings like this:
CMake Warning (dev) at /usr/share/cmake/Modules/FetchContent.cmake:1564 (cmake_parse_arguments):
The BUILD_COMMAND keyword was followed by an empty string or no value at
all. Policy CMP0174 is not set, so cmake_parse_arguments() will unset the
ARG_BUILD_COMMAND variable rather than setting it to an empty string.
Signed-off-by: raiden00pl <raiden00@railab.me>
Most tools used for compliance and SBOM generation use SPDX identifiers
This change brings us a step closer to an easy SBOM generation.
Signed-off-by: Alin Jerpelea <alin.jerpelea@sony.com>