Test BIOS is move to extended

Test BIOS needs prerequisite setup for updating BIOS.
Moved to extended test cases so that this doesn't
fail in general test bucket run.

Resolves openbmc/openbmc-test-automation#88

Change-Id: I921e8c7276a3de527ec0e947bcd9321881cdfee2
Signed-off-by: George Keishing <gkeishin@in.ibm.com>
diff --git a/tests/test_bios_update.robot b/extended/test_bios_update.robot
similarity index 100%
rename from tests/test_bios_update.robot
rename to extended/test_bios_update.robot