Update dependency "yapf" to version 0.43 or greater.

scons/requirements.txt

@@ -13,4 +13,4 @@ scons >= 4.8, < 4.9
 unittest-xml-reporting >= 3.2, < 3.3
 wheel >= 0.45, < 0.46
 yamlfix >= 1.17, < 1.18
-yapf >= 0.40, < 0.41
+yapf >= 0.43, < 0.44