Bump versions of gh actions

There are few deprecation notices shown in CI/CD UI. In order to make
sure my setup won't get broken one day, let's update used actions to be
closer to upstream.

.github/workflows/cd.yml

@@ -17,10 +17,10 @@ jobs:
           password: ${{ secrets.GITHUB_TOKEN }}
 
     steps:
-    - uses: actions/checkout@v2
+    - uses: actions/checkout@v4
 
     - name: Set up Python
-      uses: actions/setup-python@v2
+      uses: actions/setup-python@v5
       with:
         python-version: "3.10"
 
@@ -41,7 +41,7 @@ jobs:
       run: holocron run compile
 
     - name: Publish kalnytskyi.com
-      uses: peaceiris/actions-gh-pages@v3
+      uses: peaceiris/actions-gh-pages@v4
       with:
         github_token: ${{ secrets.GITHUB_TOKEN }}
         publish_dir: ./_site

.github/workflows/ci.yml

@@ -19,10 +19,10 @@ jobs:
           password: ${{ secrets.GITHUB_TOKEN }}
 
     steps:
-    - uses: actions/checkout@v2
+    - uses: actions/checkout@v4
 
     - name: Set up Python
-      uses: actions/setup-python@v2
+      uses: actions/setup-python@v5
       with:
         python-version: "3.10"