update a few more docs

CONTRIBUTING.md

@@ -1,13 +1,13 @@
 # Contributing
 
-This project uses `yarn` as a package manager. If you're adding a new dependency, ensure that the `yarn.lock` lockfile is updated and committed into your pull request.
+This project uses `pnpm` as a package manager. If you're adding a new dependency, ensure that the `pnpm-lock.yaml` lockfile is updated and committed into your pull request.
 
 ## Addon Maintenance
 
 ### Installation
 
 * `git clone` this repository
-* `yarn install`
+* `pnpm i`
 
 ### Running
 
@@ -16,7 +16,7 @@ This project uses `yarn` as a package manager. If you're adding a new dependency
 
 ### Running Tests
 
-* `yarn test:ember-compatibility` (Runs `ember try:each` to test your addon against multiple Ember versions)
+* `pnpm test:ember-compatibility` (Runs `ember try:each` to test your addon against multiple Ember versions)
 * `ember test`
 * `ember test --server`
 
@@ -35,7 +35,7 @@ npx release-it
 ### Generate API Docs
 
 TODO: use build pipeline.
-* From addon root directory `yarn docs:build`
+* From addon root directory `pnpm docs:build`
 * View built docs in `tests/dummy/public/api`
 
 ### Publishing Guides and API Docs

package.json

@@ -131,6 +131,6 @@
   },
   "volta": {
     "node": "16.19.0",
-    "yarn": "1.22.19"
+    "pnpm": "7.33.6"
   }
 }