Fix CI.yml

Author: ufechner7

.github/workflows/CI.yml

@@ -36,7 +36,6 @@ jobs:
       - name: Install matplotlib
         run: |
           sudo apt-get install -y python3-matplotlib
-          echo "PYTHON=$(which python3)" >> $GITHUB_ENV
         shell: bash
       - uses: actions/checkout@v6
       - uses: julia-actions/setup-julia@v2
@@ -45,6 +44,9 @@ jobs:
           arch: ${{ matrix.arch }}
       - uses: julia-actions/cache@v2
       - uses: julia-actions/julia-buildpkg@v1
+      - name: Build PyCall
+        run: julia --project=test -e 'ENV["PYTHON"]=""; using Pkg; Pkg.build("PyCall")'
+        shell: bash
       - uses: julia-actions/julia-runtest@v1
       - uses: julia-actions/julia-processcoverage@v1
       - uses: codecov/codecov-action@v5