Some rpm files were missing.
Most likely, you want to create these signed copies.

Missing files:
/mnt/koji/packages/drbd/9.20.2/1.el7/data/signed/3fd3ac9e/src/drbd-9.20.2-1.el7.src.rpm
/mnt/koji/packages/linstor-client/1.12.0/1/data/signed/3fd3ac9e/src/linstor-client-1.12.0-1.src.rpm
/mnt/koji/packages/python-linstor/1.12.0/1/data/signed/3fd3ac9e/src/python-linstor-1.12.0-1.src.rpm