[ruby/openssl] ssl: remove start_immediately kwarg from test helper start_server

The keyword argument is no longer used by any test cases.

ruby/openssl@2f31605d47

Author: rhenium

test/openssl/utils.rb

@@ -192,7 +192,7 @@ def readwrite_loop(ctx, ssl)
     end
   end
 
-  def start_server(verify_mode: OpenSSL::SSL::VERIFY_NONE, start_immediately: true,
+  def start_server(verify_mode: OpenSSL::SSL::VERIFY_NONE,
                    ctx_proc: nil, server_proc: method(:readwrite_loop),
                    accept_proc: proc{},
                    ignore_listener_error: false, &block)
@@ -212,7 +212,6 @@ def start_server(verify_mode: OpenSSL::SSL::VERIFY_NONE, start_immediately: true
       port = tcps.connect_address.ip_port
 
       ssls = OpenSSL::SSL::SSLServer.new(tcps, ctx)
-      ssls.start_immediately = start_immediately
 
       threads = []
       begin