ci: remove --timings flag for Next.js repo e2e tests (#2912)

This doesn't seem to provide any value for us. It just adds some test run time and
instability to our suite, since this ends up attempting to read a `test-timings.json` file
from disk (fails every time) and then makes a request to fetch timings data from a private
Vercel endpoint, which sometimes fails with a 403 for some reason.

Author: serhalp

.github/workflows/test-e2e.yml

@@ -198,7 +198,7 @@ jobs:
           NODE_ENV: production
           NEXT_EXTERNAL_TESTS_FILTERS: ${{ steps.test-filters.outputs.filters }}
           NEXT_TEST_SKIP_RETRY_MANIFEST: ${{ steps.test-filters.outputs.skip-retry }}
-        run: node run-tests.js -g ${{ matrix.group }}/${{ needs.setup.outputs.total }} -c ${TEST_CONCURRENCY} --type e2e --timings
+        run: node run-tests.js -g ${{ matrix.group }}/${{ needs.setup.outputs.total }} -c ${TEST_CONCURRENCY} --type e2e
         working-directory: ${{ env.next-path }}
 
       - name: Upload Test Results