build(deps): bump actions/checkout from 5 to 6 in the github-actions group

.github/workflows/claude.yml

@@ -31,7 +31,7 @@ jobs:
       id-token: write
     steps:
       - name: Checkout repository
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
         with:
           fetch-depth: 1
 

.github/workflows/codeql.yml

@@ -55,7 +55,7 @@ jobs:
         # your codebase is analyzed, see https://docs.github.com/en/code-security/code-scanning/creating-an-advanced-setup-for-code-scanning/codeql-code-scanning-for-compiled-languages
     steps:
     - name: Checkout repository
-      uses: actions/checkout@v5
+      uses: actions/checkout@v6
 
     # Initializes the CodeQL tools for scanning.
     - name: Initialize CodeQL

.github/workflows/release.yml

@@ -11,7 +11,7 @@ jobs:
     name: Build and verify package
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - uses: hynek/build-and-inspect-python-package@v2
 
   release:
@@ -20,7 +20,7 @@ jobs:
     needs: [build]
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - uses: softprops/action-gh-release@v2
         with:
           generate_release_notes: true

.github/workflows/test-models.yml

@@ -31,7 +31,7 @@ jobs:
         shell: bash -l {0}
 
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
         with:
           repository: PyPSA/pypsa-eur
           ref: master

.github/workflows/test.yml

@@ -18,7 +18,7 @@ jobs:
     name: Build and verify package
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
         with:
           fetch-depth: 0 # Needed for setuptools_scm
       - uses: hynek/build-and-inspect-python-package@v2
@@ -42,7 +42,7 @@ jobs:
         - windows-latest
 
     steps:
-    - uses: actions/checkout@v5
+    - uses: actions/checkout@v6
       with:
         fetch-depth: 0 # Needed for setuptools_scm
 
@@ -102,7 +102,7 @@ jobs:
     runs-on: ubuntu-latest
 
     steps:
-    - uses: actions/checkout@v5
+    - uses: actions/checkout@v6
       with:
         fetch-depth: 0 # Needed for setuptools_scm