(Reuters) - Millennium & Copthorne Hotels said uncertainty around Brexit had hurt its operations as it was finding it difficult to hire workers from the European Union for its London properties, where they currently account for half of the workforce.The operator of the Millennium, Grand Millennium, Copthorne and Kingsgate hotels also warned that 2019 would be a challenging year as renovations at its larger hotels were under way."The hospitality industry faced a range of geo-political and global..