graphql: update grades for course_score property
graphql: update grades for course_score property

Change-Id: I2d9bd9ccf409b654ef6a1764d7d91a053b1cd472
Reviewed-on: https://gerrit.instructure.com/134538
Tested-by: Jenkins
Reviewed-by: Keith T. Garner <a1a80143a840c140f31c3495ebbd9ec906e09fed@instructure.com>
QA-Review: Collin Parrish <aa381382ccdcc876f5cf7879d921ed03200f6804@instructure.com>
Product-Review: Cameron Matheson <1d572acbfa68c7c6e541c7b840d6b622e5c0dc91@instructure.com>

sfu/canvas-lms,sfu/canvas-lms,instructure/canvas-lms,sfu/canvas-lms,instructure/canvas-lms,instructure/canvas-lms,instructure/canvas-lms,djbender/canvas-lms,sfu/canvas-lms,djbender/canvas-lms,sfu/canvas-lms,sfu/canvas-lms,djbender/canvas-lms,sfu/canvas-lms,instructure/canvas-lms,instructure/canvas-lms,djbender/canvas-lms,instructure/canvas-lms