ci - use github actions checkout@v4 instead of v2

Author: sedmicha

.github/workflows/main.yml

@@ -81,7 +81,7 @@ jobs:
         yum -y install python3-docutils || yum -y install python-docutils
 
     # Checkout repository --------------------------------------------------------------------
-    - uses: actions/checkout@v2
+    - uses: actions/checkout@v4
 
     # Build libfds library  ------------------------------------------------------------------
     # Note: Master against master branch. Otherwise against debug branch.

.github/workflows/packages.yml

@@ -46,7 +46,7 @@ jobs:
         DEBIAN_FRONTEND: noninteractive
 
     # Checkout repository --------------------------------------------------------------------
-    - uses: actions/checkout@v2
+    - uses: actions/checkout@v4
 
     # Fix repository permissions
     - name: Fix repository permissions
@@ -198,7 +198,7 @@ jobs:
         yum -y install rpmdevtools
 
     # Checkout repository --------------------------------------------------------------------
-    - uses: actions/checkout@v2
+    - uses: actions/checkout@v4
 
     # Fix repository permissions
     - name: Fix repository permissions