fix(nc): remove unicode reference
fix(nc): remove unicode reference

Remove reference to unicode type which is only available in Python 2

JGrothoff/open62541,StalderT/open62541,JGrothoff/open62541,jpfr/open62541,JGrothoff/open62541,StalderT/open62541,jpfr/open62541,open62541/open62541,StalderT/open62541,open62541/open62541,jpfr/open62541,JGrothoff/open62541,open62541/open62541,open62541/open62541,StalderT/open62541,jpfr/open62541