replace deprecated toBeEmpty with toBeEmptyDOMElement

flag=none

test plan:
  - tests pass

qa risk: low

Change-Id: I71810f19ccc4590b7c4ca70a92c86ebdb14c4043
Reviewed-on: https://gerrit.instructure.com/c/canvas-lms/+/286038
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

@@ -105,7 +105,6 @@ const ignoredWarnings = [
   /Missing field moduleItem in/,
   /Please update the following components: %s/,
   /shared_brand_configs.* not called/,
-  /toBeEmpty has been deprecated/,
   /Translation for .* is missing/,
   /value provided is not in a recognized RFC2822 or ISO format/
 ]

ui/features/pace_plans/react/components/__tests__/errors.test.tsx

@@ -38,7 +38,7 @@ describe('Errors', () => {
   it('renders nothing when there are no errors', () => {
     const {container} = render(<Errors {...defaultProps} errors={{}} />)
 
-    expect(container.firstChild).toBeEmpty()
+    expect(container.firstChild).toBeEmptyDOMElement()
   })
 
   it('displays custom error messages for pre-defined categories, and generic error messages for unknown categories', () => {

ui/shared/k5/react/__tests__/StaffContactInfoLayout.test.js

@@ -70,7 +70,7 @@ describe('StaffContactInfoLayout', () => {
 
   it('renders nothing at all if staff is empty', () => {
     const {container} = render(<StaffContactInfoLayout {...getProps({staff: []})} />)
-    expect(container.firstChild).toBeEmpty()
+    expect(container.firstChild).toBeEmptyDOMElement()
   })
 
   it('renders 3 loading skeletons if isLoading set', () => {