Fixes.

node_modules/jest-leak-detector/README.md

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+# jest-leak-detector
+
+Module for verifying whether an object has been garbage collected or not.
+
+Internally creates a weak reference to the object, and forces garbage collection to happen. If the reference is gone, it meant no one else was pointing to the object.
+
+## Example
+
+```javascript
+let reference = {};
+
+const detector = new LeakDetector(reference);
+
+// Reference is held in memory.
+console.log(detector.isLeaked()); // true
+
+// We destroy the only reference to the object.
+reference = null;
+
+// Reference is gone.
+console.log(detector.isLeaked()); // false
+```