update workflows

.github/workflows/lint_python.yml

@@ -8,8 +8,6 @@ jobs:
         steps:
             - uses: actions/checkout@v4
             - uses: actions/setup-python@v5
-              with:
-                python-version: 3.12
             - name: Install dependencies
               run: pip install .[cli,dev]
             - run: mypy --install-types --non-interactive --ignore-missing-imports ./rembg

.github/workflows/publish_pypi.yml

@@ -11,8 +11,6 @@ jobs:
         steps:
             - uses: actions/checkout@v4
             - uses: actions/setup-python@v5
-              with:
-                python-version: 3.12
             - name: Install dependencies
               run: pip install .[cli,dev]
             - name: Builds and uploads to PyPI