Bump actions/checkout from 3 to 4 (#175)

Author: dependabot[bot]

.github/workflows/ci.yaml

@@ -25,7 +25,7 @@ jobs:
       matrix:
         python-version: ['3.9', '3.10', '3.11']
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - name: Create conda environment
         uses: mamba-org/provision-with-micromamba@main
         with:

.github/workflows/pypi-release.yaml

@@ -10,7 +10,7 @@ jobs:
     runs-on: ubuntu-latest
     if: github.repository == 'ncar-xdev/ecgtools'
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
         with:
           fetch-depth: 0
       - uses: actions/setup-python@v4

.github/workflows/upstream-dev-ci.yaml

@@ -24,7 +24,7 @@ jobs:
       matrix:
         python-version: ['3.10']
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - name: Create conda environment
         id: conda
         uses: mamba-org/provision-with-micromamba@main