Move to port 587 to avoid throttling, per AWS doc suggestion
Move to port 587 to avoid throttling, per AWS doc suggestion

Change-Id: Ia55658ad1d3cc02518d2f8cdbcd1e575784c5719
Signed-off-by: Diego Dompe <362eb8c2bff4070585be20c53c8ef543d5e46a6b@hpe.com>

open-switch/infra_puppet-mailman,open-switch/infra_puppet-mailman,open-switch/infra_puppet-mailman