Add a way to customize failure_retry variable

Add the possibility to set the "failure_retry" parameters
into the device dictionnary in case we would like to
re-test all the failing jobs (with "infrastructure_error" or
"job_error_exception")

Signed-off-by: Mylène Josserand <mylene.josserand@collabora.com>
1 job for 2020.02-collabora in 1 minute and 9 seconds (queued for 3 seconds)
Status Job ID Name Coverage
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passed #79479
lightweight
build debian source

00:01:09