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] <support@github.com>

.github/workflows/package.yml

@@ -13,7 +13,7 @@ jobs:
       run:
         shell: bash -l {0}
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - uses: conda-incubator/setup-miniconda@v2
         with:
           auto-update-conda: true
@@ -56,7 +56,7 @@ jobs:
       # IMPORTANT: this permission is mandatory for trusted publishing
       id-token: write
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - uses: conda-incubator/setup-miniconda@v2
         with:
           auto-update-conda: true

.github/workflows/unittest.yml

@@ -14,7 +14,7 @@ jobs:
       run:
         shell: bash -l {0}
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - uses: conda-incubator/setup-miniconda@v2
         with:
           auto-update-conda: true