rpmbuild: drop ANSI escape sequences from logs again
    
    Originally added in f4561c1498935502ae6edf8159, lost while
    reimplementing builder from Bash to Python, then partly re-added
    0573d0630386492e89a8b5.
    
    Now plus Carriage Return, Shift Out and Shift In removal.
    
    Fixes: #1961