Disable minion_id_caching

This prevents this error when building Debian package:
Could not cache minion ID: [Errno 13] Permission denied

Change-Id: Ie15eea1c9d5396e79d46b045bd5f0f22a2af39e4
diff --git a/tests/run_tests.sh b/tests/run_tests.sh
index 3f42101..6710a50 100755
--- a/tests/run_tests.sh
+++ b/tests/run_tests.sh
@@ -64,6 +64,7 @@
 file_client: local
 cachedir: ${SALT_CACHE_DIR}
 verify_env: False
+minion_id_caching: False
 
 file_roots:
   base: