Avoid hitting a firefox bug by accident. Did not mean to change cache…

…: 'immutable' - was just a way to pin down an issue and it happened to be committed with the repro of 2067

test/tests-live-query.js

@@ -6,7 +6,7 @@ import { deepEqual, isDeepEqual } from './deepEqual';
 import { isIE, promisedTest, resetDatabase } from './dexie-unittest-utils';
 
 const db = new Dexie("TestLiveQuery", {
-  cache: 'disabled' // Using immutable cache in tests because it is most likely to fail if not using properly.
+  cache: 'immutable' // Using immutable cache in tests because it is most likely to fail if not using properly.
 });
 db.version(2).stores({
     items: "id, name",