catalog: remove the is_primary field from the ColumnDesc

[st1page]

now we have the the definitions:

pub struct ColumnDesc {
    datatype: DataType,
    is_primary: bool,
}
pub struct ColumnCatalog {
    id: ColumnId,
    name: String,
    desc: ColumnDesc,
}

remove the is_primiary field from the ColumnDesc, and add the primiary_column: ColumnId in SecondaryTable and TableCatalog