The `WinError 10053` can be solved with a larger dynamic port range, if we ever run CI tests on Windows: see core#23089
The python 3.5 workaround is no longer needed since we support python >=3.9.
The other windows workaround is probably no longer necessary after bumping the server timeout for all tests (`util.py:write_config` change)
Also, move the burden of checking for a timeout to the client and
disable the timeout on the server. This should avoid intermittent issues
in slow tests (for example mining_getblocktemplate_longpoll.py, or
feature_dbcrash.py), or possibly when the server is running slow (for
example in valgrind). There shouldn't be any downside in tests caused
by a high rpcservertimeout.
This is a backport of core#23092, core#27378 and core#27418