increase build-discarder times to 180

Increasing build-discarder's days-to-keep and nums-to-keep to 180 allows the CI
to keep jobs results for at least one week considering current TF-A patchset
activity. This effectively doubles the current value which is 90.

Signed-off-by: Leonardo Sandoval <leonardo.sandoval@linaro.org>
Change-Id: I0b45bc155b0ae79098be5e5d9b7cbc4a55bb0019
2 files changed