Remove autoincrement from String column.

Passing autoincrement is not necessary because the column is a
String.

bp identity-providers

Change-Id: Ied5d8953464094d678fa934f78a7e11457ba73dc
Don't set default for a nullable column

The "description" column for identity providers is nullable, so
there's no need to set the default for the value.

bp identity-providers

Change-Id: Ib623214f029085845c26609b506f70ae91502cfc
Merge "Remove autoincrement from String column."
Merge "Don't set default for a nullable column"