yarn-plugin: import appropriate type to verify beforeWorkspacePacking signature

I realised that by default the `Plugin` type from
`@yarnpkg/core` sets the type of the `hooks`
property to `any`. This meant that there wasn't
any restriction on the hooks that could be passed,
and introduced the risk that a typo in the
`beforeWorkspacePacking` name could lead to the
hook being skipped.

This commit pulls in the appropriate type for
Hooks to verify the name and signature of the hook.

Signed-off-by: MT Lewis <mtlewis@users.noreply.github.com>

packages/yarn-plugin/package.json

@@ -34,6 +34,7 @@
     "@backstage/release-manifests": "workspace:^",
     "@yarnpkg/core": "^4.0.3",
     "@yarnpkg/fslib": "^3.0.2",
+    "@yarnpkg/plugin-pack": "^4.0.0",
     "lodash": "^4.17.21",
     "semver": "^7.6.0"
   },

packages/yarn-plugin/report.api.md

@@ -3,9 +3,10 @@
 > Do not edit this file. It is a report generated by [API Extractor](https://api-extractor.com/).
 
 ```ts
+import { Hooks } from '@yarnpkg/plugin-pack';
 import { Plugin as Plugin_2 } from '@yarnpkg/core';
 
 // @public (undocumented)
-const plugin: Plugin_2;
+const plugin: Plugin_2<Hooks>;
 export default plugin;
 ```

packages/yarn-plugin/src/index.ts

@@ -22,6 +22,7 @@
  */
 
 import { Plugin, semverUtils, YarnVersion } from '@yarnpkg/core';
+import { Hooks } from '@yarnpkg/plugin-pack';
 import { beforeWorkspacePacking } from './handlers/beforeWorkspacePacking';
 import { BackstageResolver } from './resolver/BackstageResolver';
 
@@ -43,7 +44,7 @@ if (!semverUtils.satisfiesWithPrereleases(YarnVersion, '^4.1.1')) {
 /**
  * @public
  */
-const plugin: Plugin = {
+const plugin: Plugin<Hooks> = {
   hooks: {
     beforeWorkspacePacking,
   },

yarn.lock

@@ -45427,6 +45427,7 @@ __metadata:
     "@yarnpkg/builder": ^4.0.0
     "@yarnpkg/core": ^4.0.3
     "@yarnpkg/fslib": ^3.0.2
+    "@yarnpkg/plugin-pack": ^4.0.0
     lodash: ^4.17.21
     nodemon: ^3.0.1
     semver: ^7.6.0