add runtime checks for `--fec-params` in `komodo prove`
@n.dissoubray found a bug when not passing --fec-params to komodo prove where
-
nullcannot be accessed - invalid keys in
$fec_paramsmight be accessed and crash the command
this MR adds runtime checks for the type of --fec-params, to make sure it's
- non
null - has a valid shape