contrib/examples/fix.hgrc

--- a/contrib/examples/fix.hgrc	Tue Dec 01 12:52:04 2020 -0500
+++ b/contrib/examples/fix.hgrc	Tue Dec 01 12:59:33 2020 -0500
@@ -5,7 +5,7 @@
 rustfmt:command = rustfmt +nightly
 rustfmt:pattern = set:"**.rs" - "mercurial/thirdparty/**"
 
-black:command = black --config=black.toml -
+black:command = black
 black:pattern = set:**.py - mercurial/thirdparty/**
 
 # Mercurial doesn't have any Go code, but if we did this is how we