Cleanup Rakefile (#1847)
Cleanup Rakefile (#1847)

+ Remove unnecessary gemspec definition
puma/puma,eileencodes/puma,looker/puma,looker/puma,looker/puma,eileencodes/puma,eileencodes/puma,puma/puma,eileencodes/puma,puma/puma,puma/puma,looker/puma