Bump actions/setup-python from 5 to 7

Bumps [actions/setup-python](https://github.com/actions/setup-python) from 5 to 7.
- [Release notes](https://github.com/actions/setup-python/releases)
- [Commits](https://github.com/actions/setup-python/compare/v5...v7)

---
updated-dependencies:
- dependency-name: actions/setup-python
  dependency-version: '7'
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <support@github.com>

.github/workflows/unittest.yml

diff --git a/.github/workflows/unittest.yml b/.github/workflows/unittest.yml
index 7f5a814..5b83276 100644
--- a/.github/workflows/unittest.yml
+++ b/.github/workflows/unittest.yml
@@ -42,7 +42,7 @@
         repository: apache/incubator-ponymail-foal
         path: ponymail-foal
     - name: Set up Python ${{ matrix.python-version }}
-      uses: actions/setup-python@v5
+      uses: actions/setup-python@v7
       with:
         python-version: ${{ matrix.python-version }}
     - name: Install dependencies

.github/workflows/unittest312.yml

diff --git a/.github/workflows/unittest312.yml b/.github/workflows/unittest312.yml
index d31edb3..f344cd8 100644
--- a/.github/workflows/unittest312.yml
+++ b/.github/workflows/unittest312.yml
@@ -28,7 +28,7 @@
         repository: apache/incubator-ponymail-foal
         path: ponymail-foal
     - name: Set up Python ${{ matrix.python-version }}
-      uses: actions/setup-python@v5
+      uses: actions/setup-python@v7
       with:
         python-version: ${{ matrix.python-version }}
     - name: Install dependencies