build(deps): bump actions/checkout from 3 to 4 (#14)

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]>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

Diff for: .github/workflows/ci.yml

@@ -53,7 +53,7 @@ jobs:
     steps:
 
     - name: Checkout
-      uses: actions/checkout@v3
+      uses: actions/checkout@v4
 
     - name: Setup MPI
       id:   setup-mpi
@@ -125,7 +125,7 @@ jobs:
     steps:
 
     - name: Checkout
-      uses: actions/checkout@v3
+      uses: actions/checkout@v4
 
     - name: Setup MPICH
       id:   setup1
@@ -163,7 +163,7 @@ jobs:
     steps:
 
     - name: Checkout
-      uses: actions/checkout@v3
+      uses: actions/checkout@v4
 
     - name: Setup MPICH
       id:   setup1
@@ -194,7 +194,7 @@ jobs:
     steps:
 
     - name: Checkout
-      uses: actions/checkout@v3
+      uses: actions/checkout@v4
 
     - name: Setup MPICH
       id:   setup1
@@ -236,7 +236,7 @@ jobs:
     steps:
 
     - name: Checkout
-      uses: actions/checkout@v3
+      uses: actions/checkout@v4
 
     - name: Setup Intel MPI
       id:   setup1