OS inventory fixes

Changes:
   1. Login to OS.
   2. Replace "Run" with Execute Command.
   3. Convert json file generated to pretty print file.

Resolves openbmc/openbmc-test-automation#676

Change-Id: Id181ee49cf679872dcb2f84060f2d438f49b27dc
Signed-off-by: George Keishing <gkeishin@in.ibm.com>
1 file changed