build(deps): bump actions/checkout from 3 to 4

Bumps [actions/checkout](https://github.com/actions/checkout) from 3 to 4.
- [Release notes](https://github.com/actions/checkout/releases)
- [Changelog](https://github.com/actions/checkout/blob/main/CHANGELOG.md)
- [Commits](actions/checkout@v3...v4)

---
updated-dependencies:
- dependency-name: actions/checkout
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <[email protected]>

.github/workflows/ci.yml

@@ -18,7 +18,7 @@ jobs:
     name: Linting (sphinxlint)
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@v3
+    - uses: actions/checkout@v4
     -
       uses: actions/setup-python@v4
       with:
@@ -34,7 +34,7 @@ jobs:
     name: Linting (ruff)
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@v3
+    - uses: actions/checkout@v4
     -
       uses: actions/setup-python@v4
       with:
@@ -49,7 +49,7 @@ jobs:
     name: Annotations (mypy)
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@v3
+    - uses: actions/checkout@v4
     -
       uses: actions/setup-python@v4
       with:
@@ -69,7 +69,7 @@ jobs:
         jax_default_bits: [32, 64]
       fail-fast: false
     steps:
-    - uses: actions/checkout@v3
+    - uses: actions/checkout@v4
     -
       uses: actions/setup-python@v4
       with:
@@ -86,7 +86,7 @@ jobs:
     name: Examples
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@v3
+    - uses: actions/checkout@v4
     -
       uses: actions/setup-python@v4
       with:

.github/workflows/codeql.yml

@@ -24,7 +24,7 @@ jobs:
 
     steps:
     - name: Checkout repository
-      uses: actions/checkout@v3
+      uses: actions/checkout@v4
 
     - name: Initialize CodeQL
       uses: github/codeql-action/init@v2