When you run the ``build_assemblies.py`` script, pass ``<my_local_source>`` to
the ``--push-nupkgs-local`` option:

::

    ./modules/mono/build_scripts/build_assemblies.py --godot-output-dir ./bin --push-nupkgs-local <my_local_source>

This option ensures the packages will be added to the specified local NuGet
source and that conflicting versions of the package are removed from the NuGet
cache. It's recommended to always use this option when building the C# solutions
during development to avoid mistakes.