out-of-space: Reduce the space available for test

While running the out-of-space test a dummy file is created to reduce the space available. Unfortunately, in some cases the space available is still enough to upgrade the system.

In order to fix the issue, reduce the space available to run the test.

infrastructure/apertis-issues#466 (closed)

infrastructure/apertis-issues#514 (closed)

infrastructure/apertis-issues#530 (closed)

Signed-off-by: Walter Lozano walter.lozano@collabora.com