Fix LocalDiskRepositoryTestCase to create correct type of repos

In one place LocalDiskRepositoryTestCase was ignoring the specification
whether to create a bare or non-bare repository. Fix this and fix also
one test which fails now because bare repos don't write reflogs by
default.

Change-Id: I4bcf8cf97c5b46e2f3919809eaa121a8d0e47010
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>