Resolve log folder not being created in test

There is presently an error when running `make && make test` where there is no log folder being created in the test application. This is likely due to there being no Lager command run, which would otherwise generate the folder. There is one being generated in the root folder, but that is based on lager's source code.

Perhaps there is a more elegant way to do this or the folder does not need to be generated at all, but for the time being does create it and resolves the test failure.