ci(github): Update Python to 3.8 for pre-commit checks

Fixes issue "ERROR: Package 'conventional-precommit-linter' requires a
different Python: 3.7.17 not in '>=3.8'" of all Pull Requests.

Python 3.7 support will be dropped soon in the upcoming ESP-IDF v5.2
version.

.github/workflows/pre_commit_check.yml

@@ -21,7 +21,7 @@ jobs:
       - name: Set up Python environment
         uses: actions/setup-python@master
         with:
-          python-version: v3.7
+          python-version: v3.8
       - name: Install python packages
         run: |
           pip install pre-commit