fix teacher speedgrader spec in rails 3

in rails 2, touch was calling save, and then inferring a name.
just explicitly set the name; it's not important to the spec

Change-Id: I91e95d90e89c8d411871aeadb0d476bce7fe6d74
Reviewed-on: https://gerrit.instructure.com/31775
Tested-by: Jenkins <jenkins@instructure.com>
Reviewed-by: James Williams  <jamesw@instructure.com>
Product-Review: Cody Cutrer <cody@instructure.com>
QA-Review: Cody Cutrer <cody@instructure.com>