Change default build node size to 4c x 4g for appc

appc is not able to cleanly build on a 2cx1g instance. Move up to the
next larger instance size.

Change-Id: Ib673ce0c652db603916dcd874eb01ce66c58a726
Signed-off-by: Andrew Grimberg <agrimberg@linuxfoundation.org>
2 files changed