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

@@ -13,7 +13,7 @@ jobs:
       - name: Install Git
         run: |
           apt-get update && apt-get install --yes git
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - name: Install dependencies
         run: |
           DEBIAN_FRONTEND=noninteractive TZ=Etc/UTC apt-get install --yes --no-install-recommends \
@@ -34,7 +34,7 @@ jobs:
     # Keep version in sync with rust-toolchain.toml
     container: rust:1.74.1
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - name: Install dependencies
         run: |
           rustup component add rustfmt
@@ -51,7 +51,7 @@ jobs:
       - name: Install dependencies
         run: |
           apt-get update && apt-get install --yes git libqt5designer5 python3-venv
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - name: Install Python dependencies
         run: |
           cd journalist_gui

.github/workflows/security.yml

@@ -9,7 +9,7 @@ jobs:
     # Keep version in sync with rust-toolchain.toml
     container: rust:1.74.1
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - name: Check Rust dependencies
         run: |
           make rust-audit