spec: selenium upgrade 2.42

Change-Id: I470f89d9cc9c73046dca54e451d0ee234f60d0a0
Reviewed-on: https://gerrit.instructure.com/36098
Tested-by: Jenkins <jenkins@instructure.com>
Reviewed-by: Kyle Rosenbaum <kyler@instructure.com>
Product-Review: Kyle Rosenbaum <kyler@instructure.com>
QA-Review: Kyle Rosenbaum <kyler@instructure.com>