LONDON (Reuters) -Lorries and holiday motorists heading to France from Britain were on Saturday facing long delays due to a shortage of ferries at the Port of Dover, while airport travellers have also been warned to expect queues. Many schools in Britain broke up for the two-week Easter holiday on Friday, putting more pressure on limited ferry capacity at the port, just when Britons have been freed of COVID-19 restrictions and are travelling abroad in greater numbers. Cross-channel ferry capacity between Dover, the main sea gateway to continental Europe, and the French ports of Calais and Dunk…