By Paul Sandle LONDON (Reuters) -Low-cost airline easyJet said on Monday it was cutting thousands more flights this summer after London Gatwick and Amsterdam airports reduced capacity and it battled staff shortages on the ground and in the air. The British carrier said it expected to fly about 90% of its pre-pandemic capacity in July, August and September, down from the 97% it had scheduled last month, which would have been around 160,000 flights. EasyJet said a tight labour market for crew, compounded by a 14-week wait for new staff security checks compared to around 10 weeks previously and l…