async function update(key, value) {
  try {
    const request = k8sModel.getClient('/api/v1/namespaces');
    const hexKey = Buffer.from(key).toString('hex');
    const groupInstance = Group.createGroup({
      groupname: value.groupname,
      description: value.description,
      externalName: value.externalName,
      extension: value.extension,
    });
    const groupData = {
      metadata: { name: hexKey },
      data: {
        groupname: Buffer.from(groupInstance.groupname).toString('base64'),
        description: Buffer.from(groupInstance.description).toString('base64'),
        externalName: Buffer.from(groupInstance.externalName).toString(
          'base64',
        ),
        extension: Buffer.from(
          JSON.stringify(groupInstance.extension),
        ).toString('base64'),
      },
    };
    return await request.put(`${GROUP_NAMESPACE}/secrets/${hexKey}`, groupData);
  } catch (error) {
    if (error.response) {
      throw error.response;
    } else {
      throw error;
    }
  }
}
@function update - Update a Group entry to kubernetes secrets.
@async
@param {string} key - Group name
@param {User} value - Group info
@return {Promise<Group>} A promise to the User instance.