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](actions/checkout@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>

Author: dependabot[bot]

.github/workflows/bazel_build.yml

@@ -10,7 +10,7 @@ jobs:
     runs-on: macOS-13
 
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
 
       - name: Mount bazel cache
         uses: actions/cache@v4
@@ -47,7 +47,7 @@ jobs:
     runs-on: macOS-14
 
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
 
       - name: Mount bazel cache
         uses: actions/cache@v4
@@ -84,7 +84,7 @@ jobs:
     runs-on: macOS-15
 
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
 
       - name: Mount bazel cache
         uses: actions/cache@v4
@@ -121,7 +121,7 @@ jobs:
     runs-on: ubuntu-22.04
 
     steps:
-    - uses: actions/checkout@v5
+    - uses: actions/checkout@v6
 
     - name: Mount bazel cache
       uses: actions/cache@v4
@@ -144,7 +144,7 @@ jobs:
     runs-on: ubuntu-24.04
 
     steps:
-    - uses: actions/checkout@v5
+    - uses: actions/checkout@v6
 
     - name: Mount bazel cache
       uses: actions/cache@v4
@@ -167,7 +167,7 @@ jobs:
     runs-on: windows-2022
 
     steps:
-    - uses: actions/checkout@v5
+    - uses: actions/checkout@v6
 
     - name: Mount bazel cache
       uses: actions/cache@v4
@@ -190,7 +190,7 @@ jobs:
     runs-on: windows-2025
 
     steps:
-    - uses: actions/checkout@v5
+    - uses: actions/checkout@v6
 
     - name: Mount bazel cache
       uses: actions/cache@v4

.github/workflows/codespell.yml

@@ -10,6 +10,6 @@ jobs:
     runs-on: ubuntu-latest
 
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
 
       - uses: codespell-project/actions-codespell@v2

.github/workflows/release.yml

@@ -18,7 +18,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
 
       - name: Build examples
         run: cd tests && bazel build //...