fix: remove deprecated license fmt checker

wischli · wischli · commit 644811df200d · 2022-08-05T15:51:30.000+02:00
rust-lang/rustfmt#5103
diff --git a/.rustfmt.toml b/.rustfmt.toml
@@ -4,4 +4,3 @@ imports_granularity = "Crate"
 hard_tabs = true
 max_width = 120
 wrap_comments = true
-license_template_path = "HEADER-GPL"
