ci: Fix workflow events (#106)

This was found by auditing workflows based on research published here:

https://github.com/joeyparrish/workflow-cheat-sheet

The research was prompted by a workflow bug in Shaka Streamer

Author: joeyparrish

.github/workflows/release-please.yaml

@@ -21,8 +21,10 @@ jobs:
           monorepo-tags: true
 
       - name: Checkout code
+        uses: actions/checkout@v4
+        with:
+          ref: refs/tags/${{ steps.release.outputs.tag_name }}
         if: steps.release.outputs.releases_created
-        uses: actions/checkout@v2
 
       - name: Setup Node.js
         if: steps.release.outputs.releases_created

.github/workflows/test.yaml

@@ -3,6 +3,10 @@ on:
   pull_request:
     types: [opened, synchronize, reopened]
 
+concurrency:
+  group: ${{ github.workflow }}-${{ github.event.number }}
+  cancel-in-progress: true
+
 jobs:
   build:
     name: ${{ matrix.os }}, Node.js ${{ matrix.node-version }}
@@ -23,6 +27,8 @@ jobs:
 
       - name: Checkout code
         uses: actions/checkout@v4
+        with:
+          ref: ${{ github.ref }}
 
       - name: Setup Node.js ${{ matrix.node-version }}
         uses: actions/setup-node@v4