upgrade actions/setup-node to v4 (#497)

* upgrade actions/setup-node to v4
* Fix tests uninitialized constant rack (#501)
* fix: manually insert shakapacker using "echo" instead
* manually overwrite "rack" to be v2
* update changelog

.github/workflows/dummy.yml

@@ -19,7 +19,7 @@ jobs:
       - uses: actions/checkout@v4
         with:
           persist-credentials: false
-      - uses: actions/setup-node@v3
+      - uses: actions/setup-node@v4
         with:
           node-version: '16'
       - uses: ruby/setup-ruby@v1

.github/workflows/node.yml

@@ -44,7 +44,7 @@ jobs:
         with:
           persist-credentials: false
       - name: Use Node.js ${{ matrix.node }}
-        uses: actions/setup-node@v3
+        uses: actions/setup-node@v4
         with:
           node-version: ${{ matrix.node }}
           cache: yarn

CHANGELOG.md

@@ -10,6 +10,9 @@ _next_ branch is for v8 changes
 ## [Unreleased]
 Changes since the last non-beta release.
 
+### Changed
+- Update outdated GitHub Actions to use Node.js 20.0 versions instead [PR 497](https://github.com/shakacode/shakapacker/pull/497) by [adriangohjw](https://github.com/adriangohjw).
+
 ### Fixed
 
 - Fixes failing tests for Ruby 2.7 due to `Rack::Handler::Puma.respond_to?(:config)` [PR 501](https://github.com/shakacode/shakapacker/pull/501) by [adriangohjw](https://github.com/adriangohjw)