By Lucretia Munro Following in the footsteps of royalty, Spice Girl Melanie Brown has revealed she is set to tie the knot for the third time at St Paul’s Cathedral. In October 2022, Melanie, better known as Mel B, 48, announced that she is walking down the aisle once again with her hairdresser boyfriend Rory McPhee. Mel was given the coveted award of an MBE in the same year as confirming her engagement. And since then, she has remained tight-lipped over the details of her nuptials. In a recent interview she explained: “As I have an MBE I am allowed to marry at St Paul’s. They only do a small n…