tests: update tests faking stdin
since d7f80021 (Fix support for files containing non-ascii chars., 2024-06-12) we need sys.stdin which supports reconfigure.
Before this change, we had failures like this:
======================================================================
ERROR: test_timestamp_mixed_in_timestamp (apachedex.tests.TestMalformedInput.test_timestamp_mixed_in_timestamp)
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Traceback (most recent call last):
File "/srv/slapgrid/slappart15/srv/project/apachedex/apachedex/tests.py", line 51, in test_timestamp_mixed_in_timestamp
apachedex.main()
File "/srv/slapgrid/slappart15/srv/project/apachedex/apachedex/__init__.py", line 1380, in wrapper
return func(*args, **kw)
^^^^^^^^^^^^^^^^^
File "/srv/slapgrid/slappart15/srv/project/apachedex/apachedex/__init__.py", line 1644, in main
logfile.reconfigure(
^^^^^^^^^^^^^^^^^^^
AttributeError: '_io.StringIO' object has no attribute 'reconfigure'