Fix lockfile update script

Author: jamie-osec

src/tools/update-lockfile.sh

@@ -1,18 +1,18 @@
-#!/bin/sh
+#!/bin/bash
 
 # Updates the workspaces in `.`, `library` and `src/tools/rustbook`
 # Logs are written to `cargo_update.log`
 # Used as part of regular dependency bumps
 
 set -euo pipefail
 
-echo -e "\ncompiler & tools dependencies:" > cargo_update.log
+printf "\ncompiler & tools dependencies:" > cargo_update.log
 # Remove first line that always just says "Updating crates.io index"
 cargo update 2>&1 | sed '/crates.io index/d' | \
     tee -a cargo_update.log
-echo -e "\nlibrary dependencies:" >> cargo_update.log
+printf "\nlibrary dependencies:" >> cargo_update.log
 cargo update --manifest-path library/Cargo.toml 2>&1 | sed '/crates.io index/d' | \
     tee -a cargo_update.log
-echo -e "\nrustbook dependencies:" >> cargo_update.log
+printf "\nrustbook dependencies:" >> cargo_update.log
 cargo update --manifest-path src/tools/rustbook/Cargo.toml 2>&1 | sed '/crates.io index/d' | \
     tee -a cargo_update.log