By Ali Lyon Deputy Oliver Dowden spent his Wednesday morning promoting a new website that helps people prepare for a national crisis after government research showed that more than 40 per cent of Brits do not have three days of supplies of non-perishable food and water. But it appears the UK’s superrich are already several steps ahead, with record-high enquiries about private nuclear bunkers. Amid a febrile geopolitical atmosphere and fears that wars in Ukraine and Gaza could escalate into wider conflicts, ultra high net worth individuals are asking about installing a nuclear bunker at twelve …