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Change-Id: I9184b78ab014d1493ca2729c34f35d62f2402c47
Downgrade page-object gem to 0.8.5

Fixing "Could not find page-object-0.8.6 in any of the sources" error.

Change-Id: I81e658e26432542d2f9ef6bfe783b7a4e2d9f4c7