👷 chore(ci): Extract setup step to composite action

.github/actions/setup.yml

@@ -0,0 +1,20 @@
+name: Setup
+
+description: |
+  Sets up the environment for the rest of the workflow.
+
+runs:
+  using: composite
+  steps:
+    - uses: pnpm/action-setup@v2
+      with:
+        version: 8.7.6
+
+    - uses: actions/setup-node@v3
+      with:
+        node-version-file: ".nvmrc"
+        registry-url: https://registry.npmjs.org
+        cache: pnpm
+
+    - name: Install dependencies
+      run: pnpm install --frozen-lockfile

.github/workflows/pr.yml

@@ -11,24 +11,8 @@ jobs:
     steps:
       - uses: actions/checkout@v3
 
-      - uses: pnpm/action-setup@v2
-        with:
-          version: 8.7.6
-
-      # Fetches the config package version from the `pnpm-lock.yaml` file.
-      - name: Fetch config package version
-        id: config-package-version
-        env:
-          GITMOJI_CONFIG_PACKAGE: "commitlint-config-gitmoji"
-        run: |
-          echo "CONFIG_PACKAGE=$(grep -A 2 "$GITMOJI_CONFIG_PACKAGE" pnpm-lock.yaml | awk '/version:/ {print "'"$GITMOJI_CONFIG_PACKAGE"'@" $2}')" >> "$GITHUB_OUTPUT"
-
-      # Installs only the config package required for commitlint.
-      - name: Install config package
-        env:
-          CONFIG_PACKAGE: "${{ steps.config-package-version.outputs.CONFIG_PACKAGE }}"
-        run: |
-          pnpm add -w "$CONFIG_PACKAGE"
+      - name: Setup
+        uses: ./.github/actions/setup
 
       # The validation is done based on the `commitlint.config.js` file.
       - name: Validate PR title