Update checkout/actions to v6

https://github.com/actions/checkout/releases/tag/v6.0.0
https://github.com/actions/checkout/releases/tag/v6.0.1
https://github.com/actions/checkout/releases/tag/v6.0.2

Author: ulgens

.github/workflows/docker-publish.yml

@@ -17,7 +17,7 @@ jobs:
 
         steps:
             - name: Checkout repository
-              uses: actions/checkout@v4
+              uses: actions/checkout@v6
 
             - name: Log in to the Container registry
               uses: docker/login-action@v3

.github/workflows/linters.yml

@@ -18,6 +18,6 @@ jobs:
         runs-on: ubuntu-latest
         steps:
             - name: Checkout
-              uses: actions/checkout@v4
+              uses: actions/checkout@v6
             - name: black
               uses: psf/black@stable

.github/workflows/tests.yml

@@ -26,7 +26,7 @@ jobs:
         runs-on: ubuntu-24.04
         steps:
             - name: Checkout
-              uses: actions/checkout@v4
+              uses: actions/checkout@v6
             - uses: actions/setup-python@v5
               with:
                   python-version: "3.11"
@@ -37,7 +37,7 @@ jobs:
         runs-on: ubuntu-24.04
         steps:
             - name: Checkout
-              uses: actions/checkout@v4
+              uses: actions/checkout@v6
             - uses: actions/setup-python@v5
               with:
                   python-version: "3.11"
@@ -54,7 +54,7 @@ jobs:
         runs-on: ubuntu-24.04
         steps:
             - name: Checkout
-              uses: actions/checkout@v4
+              uses: actions/checkout@v6
             - uses: actions/setup-python@v5
               with:
                   python-version: "3.11"