Bump actions/checkout from 3 to 4 (#64)

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

.github/workflows/cd.yml

@@ -47,7 +47,7 @@ jobs:
           sudo apt-get update
           sudo apt-get install -y webkit2gtk-4.1 libxdo-dev
       - name: Checking out sources
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4
       - name: Running cargo build
         run: cargo build --release --target ${{ matrix.target }}
       - name: Packaging final binary

.github/workflows/ci.yml

@@ -9,7 +9,7 @@ jobs:
     name: Test Suite
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - uses: dtolnay/rust-toolchain@stable
       - run: |
           sudo apt-get update
@@ -21,7 +21,7 @@ jobs:
     name: Rustfmt
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - uses: dtolnay/rust-toolchain@stable
         with:
           components: rustfmt
@@ -31,7 +31,7 @@ jobs:
     name: Clippy
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - uses: dtolnay/rust-toolchain@stable
         with:
           components: clippy