Function mod_value 

pub fn mod_value(
    attr_name: &str,
    source_entry: &LDAPEntry,
    source_ldap_schema: &LDAPSchema,
    source_base_dn: &str,
    destination_entry: Option<&LDAPEntry>,
    destination_base_dn: &str,
    ignore_object_classes: &[String],
) -> Result<Option<Mod<String>>, LdapOperationError>

generate an ldap3::Mod if there is a DN-valued attribute in the source entry that needs its base DN translated to the destination base DN

Errors

Returns LdapOperationError if there is an issue parsing OIDs or if a required attribute is missing.