Update actions/checkout

Author: shmokmt

.github/workflows/test.yml

@@ -9,7 +9,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout
-        uses: actions/checkout@v2 
+        uses: actions/checkout@v3 
 
       - run: sleep 5
 
@@ -25,7 +25,7 @@ jobs:
     runs-on: macos-latest
     steps:
       - name: Checkout
-        uses: actions/checkout@v2 
+        uses: actions/checkout@v3 
 
       - run: sleep 5