By Laura McGuire Business leaders are piling fresh pressure on the government to scrap its controversial tourist tax as data shows it is eating away at the UK’s GDP and banishing international visitors. FTSE 100 bosses, including Stuart Machin, the chief of M&S and Paul Marchant the boss of Primark are among the now 420 signatories writing to the Chancellor urging him to reintroduce the VAT scheme. In the letter, retail bigwigs urged Jeremy Hunt to “think again” ahead of the March Budget. “It is clear that the removal of tax-free shopping is turning into an extraordinary own- goal for the UK,”…