test_puma_server.rb - add delay for TruffleRuby, remove skip

test/test_puma_server.rb

@@ -885,7 +885,6 @@ EOF
   end
 
   def test_chunked_keep_alive_two_back_to_back
-    skip("Fails on TruffleRuby (not head)") unless !TRUFFLE || Gem::Version.new(RUBY_ENGINE_VERSION) > Gem::Version.new('22.1')
     body = nil
     content_length = nil
     server_run { |env|
@@ -909,6 +908,7 @@ EOF
     assert_equal ["HTTP/1.1 200 OK", "Content-Length: 0"], h
     assert_equal "hello", body
     assert_equal "5", content_length
+    sleep 0.05 if TRUFFLE
     assert_equal true, last_crlf_written
 
     last_crlf_writer.join