Don't Set a Default Value on Serial Fields When `notnull` is Set
Don't Set a Default Value on Serial Fields When `notnull` is Set

Serial fields already have a default value. By opting out of `notnull`
serial fields will just set the next value in the sequence.

BenMorel/dbal,drieschel/dbal,doctrine/dbal,lcobucci/dbal,vutung2311/dbal,vutung2311/dbal,lcobucci/dbal,stof/dbal,BenMorel/dbal,deeky666/dbal,Tobion/dbal,doctrine/dbal,gencer/dbal,gencer/dbal,mikeSimonson/dbal,drieschel/dbal,mikeSimonson/dbal,stof/dbal,Tobion/dbal,deeky666/dbal