By Natalie Grover (Reuters) -GSK raised its 2022 forecast for the second time this year, after third-quarter earnings and sales topped estimates, continuing its strong start as a standalone prescription medicine and vaccine business since carving out its consumer health division. After years of underperformance relative to its peers and missing out on the lucrative market for the first set of COVID-19 vaccines, GSK has delivered a string of strong results. The latest is led by a record quarter for its blockbuster shingles vaccine Shingrix and higher-than-expected revenue from its COVID therapy…