Close an open object

This method instructs the library to close an existing object; note that git_objects are owned and cached by the repository so the object may or may not be freed after this library call, depending on how agressive is the caching mechanism used by the repository.

IMPORTANT: It is not necessary to call this method when you stop using an object, since all object memory is automatically reclaimed by the repository when it is freed.

Forgetting to call git_object_close does not cause memory leaks, but it's is recommended to close as soon as possible the biggest objects (e.g. blobs) to prevent wasting memory space.