ci: update paths for workflows

Point the Python wheel building workflows to the new package directory
in `python/finufft` instead of the repository root.

.github/workflows/python_cmake.yml

@@ -58,6 +58,6 @@ jobs:
           echo CMAKE_ARGS="-DFINUFFT_ARCH_FLAGS=${{ matrix.arch_flags }}" >> $GITHUB_ENV
         shell: bash
       - name: Build
-        run: python3 -m pip install ${{ github.workspace }} --verbose
+        run: python3 -m pip install ${{ github.workspace }}/python/finufft --verbose
       - name: Test
         run: python3 -m pytest ${{ github.workspace }}/python/finufft/test

.github/workflows/python_skbuild_wheels.yml

@@ -15,6 +15,8 @@ jobs:
 
       - name: Build wheels
         uses: pypa/[email protected]
+        with:
+          package-dir: 'python/finufft'
         env:
           CIBW_BEFORE_ALL_MACOS: brew install gcc@14 fftw
           # Need following versions of GCC for compatibility with fftw
@@ -39,6 +41,8 @@ jobs:
 
       - name: Build wheels
         uses: pypa/[email protected]
+        with:
+          package-dir: 'python/finufft'
         env:
           # Make sure to install the ARM64-specific versions of FFTW and GCC.
           # Perhaps this is done automatically on the macos-14 image. We should
@@ -77,6 +81,8 @@ jobs:
 
       - name: Build wheels
         uses: pypa/[email protected]
+        with:
+          package-dir: 'python/finufft'
         env:
           # This is required to force cmake to avoid using MSVC (the default).
           # By setting the generator to Ninja, cmake will pick gcc (mingw64)