[TASK] Move fixture files from tests/

There are still some fixture files within the root tests/ directory.
The patch moves them to Fixtures/ folders below the using tests
within the affected core and backend extensions.

Change-Id: Ied23b542a65becac02c9af576728da886552484d
Resolves: #40834
Related: #40095
Releases: 6.0
Reviewed-on: http://review.typo3.org/14525
Reviewed-by: Christian Kuhn
Tested-by: Christian Kuhn