Merge pull request #747 from michaeljones/formatting

Fix black formatting warning

breathe/renderer/sphinxrenderer.py

@@ -1055,7 +1055,7 @@ def visit_class(self, node) -> List[Node]:
                     decls.append(",")
                 else:
                     first = False
-                if base.prot is not None and domain != 'cs':
+                if base.prot is not None and domain != "cs":
                     decls.append(base.prot)
                 if base.virt == "virtual":
                     decls.append("virtual")