remove non-existent pathspec from pre-commit hook (#14671)

it was added back in 6035e050e8, at which
time there were some files matching it, e.g.

6035e050e8/clippy_lints/src/lib.deprecated.rs

fixes rust-lang/rust-clippy#14670

changelog: none

util/etc/pre-commit.sh

@@ -6,7 +6,6 @@ set -e
 # Update lints
 cargo dev update_lints
 git add clippy_lints/src/lib.rs
-git add clippy_lints/src/lib.*.rs
 
 # Formatting:
 #     Git will not automatically add the formatted code to the staged changes once