Update packetgen dependency to version 4

Author: sdaubert

Gemfile

@@ -6,6 +6,11 @@ gemspec
 
 gem 'bundler', '>= 1.17', '< 3'
 
+group :development do
+  gem 'rake', '~>13.0'
+  gem 'rspec', '~>3.13'
+end
+
 group :noci do
   gem 'rubocop', '~> 1.12'
   gem 'rubocop-performance', '~> 1.13'

packetgen-plugin-ipsec.gemspec

@@ -20,8 +20,5 @@ Gem::Specification.new do |spec|
 
   spec.required_ruby_version = '>= 2.5.0'
 
-  spec.add_dependency 'packetgen', '~>3.2', '>= 3.2.1'
-
-  spec.add_development_dependency 'rake', '~> 12.3'
-  spec.add_development_dependency 'rspec', '~> 3.10'
+  spec.add_dependency 'packetgen', '~>4.0'
 end