Bump actions/checkout from 4 to 6

Bumps [actions/checkout](https://github.com/actions/checkout) from 4 to 6.
- [Release notes](https://github.com/actions/checkout/releases)
- [Changelog](https://github.com/actions/checkout/blob/main/CHANGELOG.md)
- [Commits](actions/checkout@v4...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>

Author: dependabot[bot]

.github/workflows/build.yml

@@ -35,7 +35,7 @@ jobs:
 
     steps:
 
-    - uses: actions/checkout@v4
+    - uses: actions/checkout@v6
       with:
         fetch-depth: 0
 
@@ -90,7 +90,7 @@ jobs:
 
     steps:
 
-    - uses: actions/checkout@v4
+    - uses: actions/checkout@v6
 
     - name: Set up QEMU
       id: qemu

.github/workflows/copy_conda_packages.yml

@@ -10,7 +10,7 @@ jobs:
     steps:
 
     - name: checkout
-      uses: actions/checkout@v4
+      uses: actions/checkout@v6
 
     - name: Install conda
       uses: conda-incubator/setup-miniconda@v3

.github/workflows/upload_pypi.yml

@@ -17,7 +17,7 @@ jobs:
 
     steps:
 
-    - uses: actions/checkout@v4
+    - uses: actions/checkout@v6
       with:
         fetch-depth: 0
 
@@ -42,7 +42,7 @@ jobs:
   linux_wheels:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@v4
+    - uses: actions/checkout@v6
       with:
         fetch-depth: 0
     - name: Set up Python
@@ -73,7 +73,7 @@ jobs:
   linux_aarch64_wheels:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@v4
+    - uses: actions/checkout@v6
       with:
         fetch-depth: 0
     - name: Set up Python
@@ -102,7 +102,7 @@ jobs:
   sdist:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@v4
+    - uses: actions/checkout@v6
     - name: Set up Python
       uses: actions/setup-python@v5
       with: