Extend black excludes instead of overriding

By default it will ignore things in .gitignore, which we want

Author: shanemcd

pyproject.toml

@@ -10,4 +10,4 @@ build-backend = "setuptools.build_meta"
 line-length = 160
 fast = true
 skip-string-normalization = true
-exclude = "awx_collection"
+extend-exclude = "awx_collection"