Update actions/checkout action to v4

Author: renovate[bot]

.github/workflows/tests-conda.yml

@@ -17,7 +17,7 @@ jobs:
         os: [ubuntu-latest, windows-latest]
     name: "Test: Python ${{ matrix.python-version }}, conda, ${{ matrix.os }}"
     steps:
-    - uses: actions/checkout@v3
+    - uses: actions/checkout@v4
     - uses: conda-incubator/setup-miniconda@v2
       with:
         auto-activate-base: false

.github/workflows/tests-pip.yml

@@ -17,7 +17,7 @@ jobs:
         os: [ubuntu-latest, windows-latest]
     name: "Test: Python ${{ matrix.python-version }}, pip, ${{ matrix.os }}"
     steps:
-    - uses: actions/checkout@v3
+    - uses: actions/checkout@v4
     - name: Set up Python ${{ matrix.python-version }}
       uses: actions/setup-python@v4
       with:
@@ -38,7 +38,7 @@ jobs:
         python-version: [ 3.9,  3.11 ]
     name: "Version Check: Python ${{ matrix.python-version }}"
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - name: Set up Python ${{ matrix.python-version }}
         uses: actions/setup-python@v4
         with:

.github/workflows/traffic.yml

@@ -14,7 +14,7 @@ jobs:
     # Steps represent a sequence of tasks that will be executed as part of the job
     steps:
     # Checks-out your repository under $GITHUB_WORKSPACE, so your job can access it
-    - uses: actions/checkout@v3
+    - uses: actions/checkout@v4
       with:
         ref: "traffic"