bitbake: toaster/tests: Update build test

Updated build tests in toaster, added SSTATE_MIRROR to package build, changed build directory and update test order
This builds include the core-minimal-image, on the test enviroment a smaller package was use to run the test for time purposes

(Bitbake rev: af31116f0017912fc5a58a5976c814b6b326985f)

Signed-off-by: Marlon Rodriguez Garcia <marlon.rodriguez-garcia@savoirfairelinux.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

bitbake/lib/toaster/tests/db/test_db.py

@@ -23,6 +23,7 @@
 # SOFTWARE.
 
 import sys
+import pytest
 
 try:
     from StringIO import StringIO
@@ -47,7 +48,7 @@ def capture(command, *args, **kwargs):
 def makemigrations():
     management.call_command('makemigrations')
 
-
+@pytest.mark.order(1)
 class MigrationTest(TestCase):
 
     def testPendingMigration(self):