public static void modifyLdapEntry(final LDAPConnection serverCon, final String dn,
                                       final LdapAttribute attr,
                                       final BindConnectionInitializer connInit) {
        modifyLdapEntry(serverCon, dn, attr, AttributeModification.Type.ADD, connInit);
    }
Modify ldap entry.

@param serverCon the server con
@param dn        the dn
@param attr      the attr
support/cas-server-support-ldap-core/src/test/java/org/apereo/cas/util/LdapTestUtils.java