build(npm): adhere to Husky deprecation notice

Husky v8 adds the `husky init` subcommand, and v9 changes how it handles
hooks. We no longer need the Husky preamble in our hooks, so update to
the new `init` subcommand and remove the preambles.

Change-Id: I18ea1bbaedbb4213cc04c21413d75c9757ff7986
Signed-off-by: Chris Kay <chris.kay@arm.com>
diff --git a/.husky/commit-msg b/.husky/commit-msg
index c1c9600..b5d407b 100755
--- a/.husky/commit-msg
+++ b/.husky/commit-msg
@@ -1,7 +1,4 @@
 #!/bin/sh
 
-# shellcheck source=./_/husky.sh
-. "$(dirname "$0")/_/husky.sh"
-
 "$(dirname "$0")/commit-msg.gerrit" "$@"
 "$(dirname "$0")/commit-msg.commitlint" "$@"
diff --git a/.husky/pre-commit b/.husky/pre-commit
index afcb1f6..f438ddb 100755
--- a/.husky/pre-commit
+++ b/.husky/pre-commit
@@ -1,6 +1,3 @@
 #!/bin/sh
 
-# shellcheck source=./_/husky.sh
-. "$(dirname "$0")/_/husky.sh"
-
 "$(dirname "$0")/pre-commit.copyright" "$@"
diff --git a/package-lock.json b/package-lock.json
index 7753a38..e60c44e 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -7,7 +7,6 @@
     "": {
       "name": "trusted-firmware-a",
       "version": "2.10.0",
-      "hasInstallScript": true,
       "license": "BSD-3-Clause",
       "devDependencies": {
         "@commitlint/cli": "^19.0.0",
diff --git a/package.json b/package.json
index 43c897e..7ad5c58 100644
--- a/package.json
+++ b/package.json
@@ -5,7 +5,7 @@
   "type": "module",
   "private": true,
   "scripts": {
-    "postinstall": "husky install",
+    "prepare": "husky",
     "release": "standard-version"
   },
   "engines": {