Victoria Beckham performed a Spice Girls song on karaoke. The 48-year-old star – who shot to fame as Posh Spice in the 1990s girl group alongside Geri Halliwell, Mel B, Emma Bunton and Melanie C – is on holiday with her footballer husband David and grabbed the microphone in a club to give a rendition of classic track ‘Stop.’ Alongside a video clip of the performance, David wrote on Instagram: “Karaoke night with the one a only Posh Spice”(sic) The ‘Not Such an Innocent Girl’ singer – who since her days in pop music has launched a career in fashion design and declined to join the ‘Wannabe’ hitm…