Despite their relationship being strained recently, Prince Harry and Meghan Markle have sent their congratulations to Prince William and Kate Middleton, who are celebrating their tenth wedding anniversary.The Duke and Duchess of Sussex, who are set to take part in a Covid vaccine concert, reached out to William, 28, and Kate, 29, privately, a spokesperson confirmed to Daily Beast.The insider did not reveal any information about what was in the message that Harry, 36, and Meghan, 39, had sent