tests/unit: Bump test-crypto-block test timeout to 5 minutes

tests/unit: Bump test-crypto-block test timeout to 5 minutes

When running the tests in slow mode on a very loaded system and with
--enable-debug, the test-crypto-block can take longer than 4 minutes.
Bump the timeout to 5 minutes to make sure that it also passes in
such situations.

Signed-off-by: Thomas Huth <thuth@redhat.com>
Message-Id: <20231215070357.10888-15-thuth@redhat.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
(cherry picked from commit e1b363e328d559cd5f86d3d1d7b84d0154e153d3)
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>