Use actions checkout v3

Author: natanfelles

.github/workflows/tests.yml

@@ -18,7 +18,7 @@ jobs:
 
     steps:
       - name: Checkout
-        uses: actions/checkout@v2
+        uses: actions/checkout@v3
 
       - name: Setup PHP
         uses: shivammathur/setup-php@v2
@@ -70,7 +70,7 @@ jobs:
 
     steps:
       - name: Checkout
-        uses: actions/checkout@v2
+        uses: actions/checkout@v3
 
       - name: Setup PHP
         uses: shivammathur/setup-php@v2