Increase wait time for better average reading
Increase wait time for better average reading

Power readings are updated every 30 seconds and when booting host,
it could take longer than a minute to stabilize the power usage.

Change-Id: I0fffad5236f67e13626635af5f85dea44cc26bde
Signed-off-by: George Keishing <bef0a9ecac45fb57611777c8270153994e13fd2e@in.ibm.com>

openbmc/openbmc-test-automation,openbmc/openbmc-test-automation