revert checkout versions

Author: sgd2z

.github/workflows/bench.yaml

@@ -14,7 +14,7 @@ jobs:
     name: Run benchmarks 
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@v4
 
       - uses: actions/setup-python@v5
         with:

.github/workflows/ci.yaml

@@ -22,7 +22,7 @@ jobs:
     env:
       PYTHON: ${{ matrix.python-version }}
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
         with:
           fetch-depth: 0 # fetch all history for setuptools_scm to be able to read tags