update setup-node action

Author: BenoitZugmeyer

.github/workflows/ci.yml

@@ -1,5 +1,18 @@
 name: ci
 
+install-steps: &install-steps
+  - uses: actions/checkout@ee0669bd1cc54295c223e0bb666b733df41de1c5 # v2.7.0
+
+  - uses: actions/setup-node@7c12f8017d5436eb855f1ed4399f037a36fbd9e8 # v2.5.2
+    with:
+      node-version: 20
+
+  - name: enable corepack
+    run: corepack enable
+
+  - name: Install dependencies
+    run: yarn
+
 on:
   push:
   pull_request:
@@ -9,12 +22,7 @@ jobs:
   check-is-built:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@ee0669bd1cc54295c223e0bb666b733df41de1c5 # v2.7.0
-      - uses: actions/setup-node@7c12f8017d5436eb855f1ed4399f037a36fbd9e8 # v2.5.2
-        with:
-          node-version: '20'
-      - name: yarn install
-        run: yarn install
+      <<: *install-steps
 
       - name: yarn build
         run: yarn build
@@ -27,25 +35,15 @@ jobs:
   prettier:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@ee0669bd1cc54295c223e0bb666b733df41de1c5 # v2.7.0
-      - uses: actions/setup-node@7c12f8017d5436eb855f1ed4399f037a36fbd9e8 # v2.5.2
-        with:
-          node-version: '20'
-      - name: yarn install
-        run: yarn install
+      <<: *install-steps
 
       - name: format all files
         run: yarn format
 
   validate:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@ee0669bd1cc54295c223e0bb666b733df41de1c5 # v2.7.0
-      - uses: actions/setup-node@7c12f8017d5436eb855f1ed4399f037a36fbd9e8 # v2.5.2
-        with:
-          node-version: '20'
-      - name: yarn install
-        run: yarn install
+      <<: *install-steps
 
       - name: validate script integration tests
         run: node scripts/validate.integration-tests.mjs