Bump actions/checkout from 3 to 4 in /.github/workflows (#352)

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]

.github/workflows/maven.yml

@@ -41,7 +41,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout repo
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4
 
       - name: Set up JDK
         uses: actions/setup-java@v3
@@ -61,7 +61,7 @@ jobs:
         profile: [ 'cockroachdb', 'mariadb', 'mysql', 'postgres', 'spanner', 'phoenix', 'sqlserver', 'sqlite' ]
     steps:
     - name: Checkout repo
-      uses: actions/checkout@v3
+      uses: actions/checkout@v4
 
     - name: Set up JDK
       uses: actions/setup-java@v3
@@ -459,7 +459,7 @@ jobs:
           PGPASSWORD=password dropdb -h localhost -U admin benchbase --if-exists
           PGPASSWORD=password createdb -h localhost -U admin benchbase
       - name: Checkout repo
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4
       # https://github.com/actions/cache/blob/master/examples.md#java---maven
       - name: Cache local Maven repository
         uses: actions/cache@v3