[test] Replace logilab-common's with_tempdir by tempfile.TemporaryDirectory
logilab-common's with_tempdir decorator, which is considered harmful (see
https://www.logilab.org/ticket/8267966).
Rely on backports.tempfile to provide TemporaryDirectory on Python 2.
Re-export it in testlib module for convenience.
addressbook
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blog
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company
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mailinglist
person
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