meta: update pre-commit

.cargo-husky/hooks/pre-commit

@@ -1,6 +1,6 @@
 #!/bin/sh
 set -e
-for file in $(git diff --name-only --cached | grep '.rs'); do
+for file in $(git diff --name-only --cached --diff-filter=d | grep '\.rs$'); do
   rustfmt --edition 2018 $file # this will NEVER age poorly
   git add "$file"
 done