Support for the Ruby 2.4 series has ended. See here for reference.
SystemExit
Raised to indicate that a system exit should occur with the specified exit_code
Creates a new SystemExitException with the given exit_code
# File rubygems/exceptions.rb, line 206
def initialize(exit_code)
@exit_code = exit_code
super "Exiting RubyGems with exit_code #{exit_code}"
end