This commit applies the Black format to the `dccommon`
files to ensure that it adheres to the Black code style guidelines.
Test Plan:
PASS: Success in stx-distcloud-tox-black
Story: 2011149
Task: 50411
Change-Id: I98171db7dcedbda57fd78059d45aec93e5c9cabd
Signed-off-by: Hugo Brito <hugo.brito@windriver.com>