Bump actions/checkout from 3 to 4 (#94)

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>

Author: dependabot[bot]

.github/workflows/main.yml

@@ -23,7 +23,7 @@ jobs:
           poetry-version: [1.5.1]
     steps:
       - name: Checkout repository
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4
       - name: Setup Python 3.9
         uses: actions/setup-python@v4
         with:
@@ -65,7 +65,7 @@ jobs:
         shell: bash
     steps:
       - name: Checkout repository
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4
       - name: Setup Python ${{ matrix.python-version }}
         uses: actions/setup-python@v4
         with:
@@ -123,7 +123,7 @@ jobs:
         shell: bash
     steps:
       - name: Checkout repository
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4
       - name: Setup Python ${{ matrix.python-version }}
         uses: actions/setup-python@v4
         with:
@@ -168,7 +168,7 @@ jobs:
     if: startsWith(github.ref, 'refs/tags/')
     steps:
       - name: Checkout repository
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4
       - name: Setup Python ${{ matrix.python-version }}
         uses: actions/setup-python@v4
         with:

.github/workflows/pr_checks.yml

@@ -22,7 +22,7 @@ jobs:
         run: |
           echo "PR_NUMBER=${{ github.event.pull_request.number }}" >> $GITHUB_ENV
           echo "TAGGED_MILESTONE=${{ github.event.pull_request.milestone.title }}" >> $GITHUB_ENV
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
         with:
           fetch-depth: '0'
       - name: Check that CHANGELOG has been updated