fix(docs): incorrect indentation in change log

Readthedocs job[1] which builds tf-a-tests documentation has been
failing silently since few days with the following message:

	WARNING: Unexpected indentation

This patch makes the necessary fix.

[1] https://readthedocs.org/projects/trustedfirmware-a-tests/builds/20363586/

Signed-off-by: Madhukar Pappireddy <madhukar.pappireddy@arm.com>
Change-Id: Icf762428d3e2b57290c6e8e34a4cfeb897dcf140
1 file changed