Update github action version

Author: mbeijen

.github/workflows/unittest.yml

@@ -30,7 +30,7 @@ jobs:
       image: perldocker/perl-tester:${{ matrix.perl-version }}
 
     steps:
-      - uses: actions/checkout@v1
+      - uses: actions/checkout@v5
       - name: perl -V
         run: perl -V
       - name: Install OS Dependencies