Bump actions/checkout from 1 to 4

Bumps [actions/checkout](https://github.com/actions/checkout) from 1 to 4.
- [Release notes](https://github.com/actions/checkout/releases)
- [Changelog](https://github.com/actions/checkout/blob/main/CHANGELOG.md)
- [Commits](actions/checkout@v1...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/codecov_report.yaml

@@ -15,7 +15,7 @@ jobs:
     runs-on: macos-latest
 
     steps:
-    - uses: actions/checkout@v2
+    - uses: actions/checkout@v4
     - name: Set up Python 3.6
       uses: actions/setup-python@v1
       with:

.github/workflows/lint_mypy.yml

@@ -15,7 +15,7 @@ jobs:
   lint:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@v1
+    - uses: actions/checkout@v4
     - uses: actions/setup-python@v1
       with:
         python-version: '3.x'
@@ -25,7 +25,7 @@ jobs:
   mypy:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@v1
+    - uses: actions/checkout@v4
     - uses: actions/setup-python@v1
       with:
         python-version: '3.x'

.github/workflows/macos_ci.yml

@@ -18,7 +18,7 @@ jobs:
         python-version: [3.6, 3.7, 3.8]
 
     steps:
-    - uses: actions/checkout@v2
+    - uses: actions/checkout@v4
     - name: Set up Python ${{ matrix.python-version }}
       uses: actions/setup-python@v1
       with:

.github/workflows/windows_ci.yml

@@ -18,7 +18,7 @@ jobs:
         python-version: [3.6, 3.7, 3.8]
 
     steps:
-    - uses: actions/checkout@v2
+    - uses: actions/checkout@v4
     - name: Set up Python ${{ matrix.python-version }}
       uses: actions/setup-python@v1
       with: