CI: Update actions/checkout

Author: mrkn

.github/workflows/ci.yml

@@ -62,7 +62,7 @@ jobs:
         #- { os: macos-latest   , ruby: debug , python: "3.x" , python_architecture: x64 , venv: "" }
 
     steps:
-    - uses: actions/checkout@v2
+    - uses: actions/checkout@v3
       with:
         fetch-depth: 1
 

.github/workflows/windows.yml

@@ -33,7 +33,7 @@ jobs:
         #- { os: windows-latest , ruby: mswin , python: 3.x , python_architecture: x64 }
 
     steps:
-    - uses: actions/checkout@v2
+    - uses: actions/checkout@v3
       with:
         fetch-depth: 1