Fix memory bugs with bubblesort implementation
Fix memory bugs with bubblesort implementation

This commit fixes memory bugs present in the bubblesort implementation
('bubblesort'). The bug was due to allocating a single `void*` pointer
to a `void*` pointer (instead of the correct `void**` pointer).

jmcph4/jcrl,jmcph4/jcrl,jmcph4/jcrl,jmcph4/jcrl