Composite of effective changes from:
I36f8fc8130ed914e8a2c2a11c9679144d931ad73
Ia6dac22081c92bbccc803f233dd53740f6b48abb
I820bba1347954b659fd7469ed542f98ef0a6eaf0
Ultimately to reduce CI VM count in terms of memory
utilization and disk utilization in order to get
consumption into a safe range to prevent
out of memory and out of disk space conditions.
Also disables automated erasure on one of the jobs
where it was disabled on other branches as it is
already tested elsewhere in the gate.
Change-Id: Ic9f3ddc9cd48c5a973996a4136d9832f869c0b08