Previously if a user tried to pass a command line build
option that contained a '%' character the command line
parser assumed that there was string interpolation to be
done. As there is no sense in such a scenario no code
provides any input for the interpolation. This then leads to
a failure.
In this commit we specifically override the defaults in
ConfigParser and set interpolation to None, which disables
command line build option interpolation.
Fixes#6157
Paulo Neves