ci: apply security best practices (#129)

Co-authored-by: Ulises Gascón <ulisesgascongonzalez@gmail.com>

Author: step-security-bot

.github/dependabot.yml

@@ -0,0 +1,15 @@
+version: 2
+updates:
+  - package-ecosystem: github-actions
+    directory: /
+    schedule:
+      interval: monthly
+
+  - package-ecosystem: npm
+    directory: /
+    schedule:
+      interval: monthly
+    open-pull-requests-limit: 10
+    ignore:
+      - dependency-name: "*"
+        update-types: ["version-update:semver-major"]

.github/workflows/ci.yml

@@ -4,8 +4,14 @@ on:
 - pull_request
 - push
 
+permissions:
+  contents: read
+
 jobs:
   test:
+    permissions:
+      checks: write  # for coverallsapp/github-action to create new checks
+      contents: read  # for actions/checkout to fetch code
     runs-on: ubuntu-latest
     strategy:
       matrix:
@@ -128,7 +134,7 @@ jobs:
           node-version: "22.0"
 
     steps:
-    - uses: actions/checkout@v4
+    - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
 
     - name: Install Node.js ${{ matrix.node-version }}
       shell: bash -eo pipefail -l {0}
@@ -196,19 +202,21 @@ jobs:
       run: npm run lint
 
     - name: Collect code coverage
-      uses: coverallsapp/github-action@master
+      uses: coverallsapp/github-action@09b709cf6a16e30b0808ba050c7a6e8a5ef13f8d # master
       if: steps.list_env.outputs.nyc != ''
       with:
         github-token: ${{ secrets.GITHUB_TOKEN }}
         flag-name: run-${{ matrix.test_number }}
         parallel: true
 
   coverage:
+    permissions:
+      checks: write  # for coverallsapp/github-action to create new checks
     needs: test
     runs-on: ubuntu-latest
     steps:
     - name: Upload code coverage
-      uses: coverallsapp/github-action@master
+      uses: coverallsapp/github-action@09b709cf6a16e30b0808ba050c7a6e8a5ef13f8d # master
       with:
         github-token: ${{ secrets.github_token }}
         parallel-finished: true