provide correct submissions prop type

flag=none

test plan:
  - n/a

qa risk: low

Change-Id: I78ab878ee2391ca0c7494d0921bbd9fdcb370c63
Reviewed-on: https://gerrit.instructure.com/c/canvas-lms/+/274134
Tested-by: Service Cloud Jenkins <svc.cloudjenkins@instructure.com>
Reviewed-by: Omar Soto-Fortuño <omar.soto@instructure.com>
QA-Review: Omar Soto-Fortuño <omar.soto@instructure.com>
Product-Review: Omar Soto-Fortuño <omar.soto@instructure.com>

jest/jest-setup.js

@@ -74,7 +74,6 @@ const ignoredErrors = [
   /Invalid prop `returnFocusTo` of type `DeprecatedComponent` supplied to `(CourseHomeDialog|HomePagePromptContainer)`/,
   /Invalid prop `selectedDate` of type `date` supplied to `CanvasDateInput`/,
   /Invalid prop `shares\[0\].content_export.id` of type `number` supplied to `ReceivedTable`/,
-  /Invalid prop `submissions\[0\].submissionDraft.submissionAttempt` of type `number` supplied to `StudentsTable`/,
   /Invalid prop `value` of type `object` supplied to `CanvasSelect`/,
   /Invariant Violation/,
   /It looks like you're using the wrong act/,

ui/features/assignments_show_teacher/react/components/StudentsTab/__tests__/StudentsTable.test.js

@@ -111,7 +111,7 @@ it('indicates when a submission draft is present', () => {
   const submission = mockSubmission({
     nodes: [user],
     submissionHistories: {nodes: []},
-    submissionDraft: {submissionAttempt: 0}
+    submissionDraft: {submissionAttempt: '0'}
   })
   const assignment = mockAssignment()