fix: Remove trailing whitespace from testpypi workflow

Author: Claude Subagent

.github/workflows/testpypi.yml

@@ -14,16 +14,16 @@ jobs:
       - uses: actions/setup-python@v5
         with:
           python-version: "3.12"
-      
+
       - name: Install build tools
         run: python -m pip install --upgrade build twine
-      
+
       - name: Build distributions
         run: python -m build
-      
+
       - name: Check distributions
         run: twine check dist/*
-      
+
       - name: Publish to TestPyPI
         uses: pypa/gh-action-pypi-publish@release/v1
         with:
@@ -41,15 +41,15 @@ jobs:
       - uses: actions/setup-python@v5
         with:
           python-version: ${{ matrix.python-version }}
-      
+
       - name: Wait for TestPyPI package
         run: sleep 30
-      
+
       - name: Install from TestPyPI
         run: |
           pip install --index-url https://test.pypi.org/simple/ \
             --extra-index-url https://pypi.org/simple/ \
             zarr
-      
+
       - name: Test import
         run: python -c "import zarr; print(zarr.__version__)"