Fix coverage r21763/#2467

git-svn-id: https://chaste.cs.ox.ac.uk/svn/chaste/trunk@21794 b5f69653-2bf5-0310-8201-b0dafb8e1405
Revert r21761 in which test fails in parallel

git-svn-id: https://chaste.cs.ox.ac.uk/svn/chaste/trunk@21795 b5f69653-2bf5-0310-8201-b0dafb8e1405