Fix pessimistic version contraint in podspec

Author: camelpunch

RMQClient.podspec

@@ -14,5 +14,5 @@ Pod::Spec.new do |s|
   s.source           = { :git => "https://github.com/rabbitmq/rabbitmq-objc-client.git", :tag => "v#{s.version}" }
   s.source_files     = "RMQClient", "RMQClient/**/*.{h,m}"
   s.dependency       "JKVValue"
-  s.dependency       "CocoaAsyncSocket", "~> 7.4"
+  s.dependency       "CocoaAsyncSocket", "~> 7.4.0"
 end