Tracing Flaky test

[ehsannas]

This client-side tracing test

nodejs-firestore/dev/system-test/tracing.ts

Lines 814 to 824 in 1ddb62e

	it('document reference update()', async () => {
	await runFirestoreOperationInRootSpan(() =>
	firestore.collection('foo').doc('bar').update('foo', 'bar2')
	);
	await waitForCompletedSpans(3);
	expectSpanHierarchy(
	SPAN_NAME_TEST_ROOT,
	SPAN_NAME_DOC_REF_UPDATE,
	SPAN_NAME_BATCH_COMMIT
	);
	});

assumes that the foo/bar document exists -- which it shouldn't. It sometimes passes because most often the previous test creates that document:

nodejs-firestore/dev/system-test/tracing.ts

Lines 802 to 805 in 1ddb62e

	it('document reference set()', async () => {
	await runFirestoreOperationInRootSpan(() =>
	firestore.collection('foo').doc('bar').set({foo: 'bar'})
	);

I'll fix this test.