Fix variable name in parse and verify example
Fix variable name in parse and verify example

NicheInc/jwt-go,wangfakang/jwt-go,cosiner/zerver_jwt,itsjamie/jwt-go,dgrijalva/jwt-go,insionng/jwt-go,vektra/jwt-go,agaurav/jwt-go,nabeken/jwt-go,missmp/jwt-go