docs(ngRepeat): fix formatting

src/ng/directive/ngRepeat.js

@@ -97,7 +97,7 @@
  *     mapped to the same DOM element, which is not possible.)  Filters should be applied to the expression,
  *     before specifying a tracking expression.
  *
- *     For example: `item in items` is equivalent to `item in items track by $id(item)'. This implies that the DOM elements
+ *     For example: `item in items` is equivalent to `item in items track by $id(item)`. This implies that the DOM elements
  *     will be associated by item identity in the array.
  *
  *     For example: `item in items track by $id(item)`. A built in `$id()` function can be used to assign a unique