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/ci-linux.yml

@@ -20,13 +20,13 @@ jobs:
           sudo apt-get update --assume-yes
           sudo apt-get install --assume-yes --no-install-recommends clang g++ git make libc++-dev libc++abi-dev pkg-config
       - name: Checkout InspIRCd@insp3
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4
         with:
           repository: 'inspircd/inspircd'
           ref: 'insp3'
           path: 'inspircd'
       - name: Checkout self
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4
         with:
           path: 'contrib'
       - name: (Pull Request) Set the build target to only the changed modules

.github/workflows/ci-macos.yml

@@ -19,13 +19,13 @@ jobs:
           brew update || true
           brew install pkg-config
       - name: Checkout InspIRCd@insp3
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4
         with:
           repository: 'inspircd/inspircd'
           ref: 'insp3'
           path: 'inspircd'
       - name: Checkout self
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4
         with:
           path: 'contrib'
       - name: (Pull Request) Set the build target to only the changed modules

.github/workflows/regen-modules.yml

@@ -6,7 +6,7 @@ jobs:
     if: github.repository == 'inspircd/inspircd-contrib'
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
         with:
           fetch-depth: 0
       - name: Regenerate the module list