CICD: Update checkout action to v4

Author: stephane-caron

.github/workflows/ci.yml

@@ -14,7 +14,7 @@ jobs:
 
         steps:
             - name: "Checkout sources"
-              uses: actions/checkout@v3
+              uses: actions/checkout@v4
               with:
                   submodules: recursive
 
@@ -45,7 +45,7 @@ jobs:
 
         steps:
             - name: "Checkout sources"
-              uses: actions/checkout@v3
+              uses: actions/checkout@v4
 
             - name: "Set up Python"
               uses: actions/setup-python@v4
@@ -75,7 +75,7 @@ jobs:
 
         steps:
             - name: "Checkout sources"
-              uses: actions/checkout@v3
+              uses: actions/checkout@v4
 
             - name: "Set up Python ${{ matrix.python-version }}"
               uses: actions/setup-python@v4

.github/workflows/docs.yml

@@ -19,7 +19,7 @@ jobs:
             contents: write
         steps:
             - name: "Checkout Git repository"
-              uses: actions/checkout@v3
+              uses: actions/checkout@v4
 
             - name: "Install Conda environment with Micromamba"
               uses: mamba-org/setup-micromamba@v1

CHANGELOG.md

@@ -5,10 +5,11 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
-## Unreleased
+## [Unreleased]
 
 ### Changed
 
+- CICD: Update checkout action to v4
 - Update supported Python versions to 3.9–3.12
 
 ## [3.1.0] - 2024-10-28