3ee0723 common, keygen: logging shouldn't affect stdout

Authored and Committed by praiskup a year ago
    common, keygen: logging shouldn't affect stdout
    
    Backend's sign command failed with:
    '/bin/sign -h dummy-pkg-20221113_1352-1.src.rpm' failed with: packet is not a signature
    
    Merges: #2369
    Complements: 7467c5682dd79e5818cb276eaea1d5b4969f0105
    
        
file modified
+4 -5
file modified
+1 -1