Fix conflict with resolv-replace gem

Closes #987

In version 3.2.7 socket_timeout option was introduced for TCPSocket.

This works unless `resolv-replace` gem is loaded (which was added to
ruby standard library since version 3.0.0).

This commit adds another check besides the ruby version check to avoid
breaking dalli for applications that have `resolv-replace` gem required.

lib/dalli/socket.rb

@@ -88,7 +88,8 @@ class TCP < TCPSocket
       # options - supports enhanced logging in the case of a timeout
       attr_accessor :options
 
-      if RUBY_VERSION >= '3.0'
+      if RUBY_VERSION >= '3.0' &&
+          !::TCPSocket.private_instance_methods.include?(:original_resolv_initialize)
         def self.open(host, port, options = {})
           sock = new(host, port, connect_timeout: options[:socket_timeout])
           sock.options = { host: host, port: port }.merge(options)