tutorial: use https links NO_CHANGELOG=internal NO_DOC=internal NO_TEST=internal

test: fix flaky viny/tx_gap_lock test The `cmp_tuple` helper function is broken - it assumes that all tuple fields, including the payload, are numeric. It isn't true - the payload field is either nil or string. This results in a false-positive test failure: ``` error: '[string "function cmp_tuple(t1, t2) for i = 1, PAY..."]:1: attempt to compare nil with string' ``` Closes #6336 NO_DOC=test NO_CHANGELOG=test

test-run: bump to new version Bump test-run to new version with the following improvements: - Fix issue with not detecting successful server start [1] [1] tarantool/test-run#343 NO_DOC=testing stuff NO_TEST=testing stuff NO_CHANGELOG=testing stuff

test: set shutdown timeout to infinity for default luatest instance With the default shutdown timeout of 3 seconds, a test that leaves behind asynchronous requests would still pass, but it would take longer to finish, because the server instance started by Tarantool would have to wait for the dangling requests to complete. Setting the timeout to infinity will result in a hang, making us fix the test. Infinite timeout is also good for catching bugs like #7225 and #7256. We don't set the timeout for diff and TAP tests because those are deprecated and shouldn't be used for writing new tests. Nevertheless, I manually checked that none of them hangs if the timeout is set to infinity. Closes #6820 NO_DOC=test NO_CHANGELOG=test

iostream: shutdown socket fd before close If a socket fd is shared by a child process, closing it in the parent will not shut down the underlying connection. As a result, the server may hang executing the graceful shutdown protocol. Fix this problem by explicitly shutting down the connection socket fd before closing it. This is a recommended way to terminate a Unix socket connection, see http://www.faqs.org/faqs/unix-faq/socket/#:~:text=2.6.%20%20When%20should%20I%20use%20shutdown()%3F Closes #7256 NO_DOC=bug fix