support/testing: fix flake8 issue in CPE ID test

Signed-off-by: Yann E. MORIN <yann.morin.1998@free.fr>

support/testing/tests/core/test_cpeid.py

@@ -2,6 +2,7 @@ import infra
 import subprocess
 import json
 
+
 class CpeIdTest(infra.basetest.BRConfigTest):
     config = ""
     br2_external = [infra.filepath("tests/core/cpeid-br2-external")]