Bump actions/checkout from 5 to 6

Bumps [actions/checkout](https://github.com/actions/checkout) from 5 to 6.
- [Release notes](https://github.com/actions/checkout/releases)
- [Changelog](https://github.com/actions/checkout/blob/main/CHANGELOG.md)
- [Commits](https://github.com/actions/checkout/compare/v5...v6)

---
updated-dependencies:
- dependency-name: actions/checkout
  dependency-version: '6'
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <support@github.com>

.github/workflows/ci_cd.yml

@@ -23,7 +23,7 @@ jobs:
     runs-on: ubuntu-24.04
     steps:
       - name: Check out repository
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
 
       - name: Set up Python
         uses: actions/setup-python@v6
@@ -47,7 +47,7 @@ jobs:
           - python
     steps:
       - name: Check out repository
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
 
       - name: Initialize CodeQL
         uses: github/codeql-action/init@v4
@@ -67,7 +67,7 @@ jobs:
     runs-on: ubuntu-24.04
     steps:
       - name: Check out repository
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
 
       - name: Set up Python
         uses: actions/setup-python@v6
@@ -90,7 +90,7 @@ jobs:
     runs-on: ubuntu-24.04
     steps:
       - name: Check out repository
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
 
       - name: Set up Python
         uses: actions/setup-python@v6
@@ -123,7 +123,7 @@ jobs:
           - ubuntu-24.04
     steps:
       - name: Check out repository
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
 
       - name: Set up Python
         uses: actions/setup-python@v6
@@ -154,7 +154,7 @@ jobs:
     runs-on: ubuntu-24.04
     steps:
       - name: Check out repository
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
 
       - name: Build Docker image
         run: docker build . -t nettacker
@@ -231,7 +231,7 @@ jobs:
           sudo apt-get install docker-ce=5:${{ matrix.docker-version }} docker-ce-cli=5:${{ matrix.docker-version }}
 
       - name: Check out repository
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
 
       - name: Print Docker version
         run: docker -v
@@ -251,7 +251,7 @@ jobs:
     runs-on: ubuntu-24.04
     steps:
       - name: Check out repository
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
 
       - name: Login to Docker Hub
         uses: docker/login-action@v3
@@ -282,7 +282,7 @@ jobs:
     runs-on: ubuntu-24.04
     steps:
       - name: Check out repository
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
 
       - name: Set up QEMU
         uses: docker/setup-qemu-action@v3