ci: install setuptools explicitly

Author: ntamas

.github/workflows/build.yml

@@ -32,7 +32,7 @@ jobs:
       - name: Build wheels (manylinux)
         uses: pypa/cibuildwheel@v2.17.0
         env:
-          CIBW_BEFORE_BUILD: "yum install -y flex bison libxml2-devel zlib-devel cairo-devel && pip install -U cmake pip wheel && python setup.py build_c_core"
+          CIBW_BEFORE_BUILD: "yum install -y flex bison libxml2-devel zlib-devel cairo-devel && pip install -U cmake pip setuptools wheel && python setup.py build_c_core"
           CIBW_BUILD: "*-manylinux_${{ matrix.wheel_arch }}"
           # Skip tests for Python 3.10 onwards because SciPy does not have
           # 32-bit wheels for Linux
@@ -41,7 +41,7 @@ jobs:
       - name: Build wheels (musllinux)
         uses: pypa/cibuildwheel@v2.17.0
         env:
-          CIBW_BEFORE_BUILD: "apk add flex bison libxml2-dev zlib-dev cairo-dev && pip install -U cmake pip wheel && python setup.py build_c_core"
+          CIBW_BEFORE_BUILD: "apk add flex bison libxml2-dev zlib-dev cairo-dev && pip install -U cmake pip setuptools wheel && python setup.py build_c_core"
           CIBW_BUILD: "*-musllinux_${{ matrix.wheel_arch }}"
           CIBW_TEST_COMMAND: "cd {project} && pip install --prefer-binary '.[test-musl]' && python -m pytest -v tests"
 
@@ -66,7 +66,7 @@ jobs:
       - name: Build wheels (manylinux)
         uses: pypa/cibuildwheel@v2.17.0
         env:
-          CIBW_BEFORE_BUILD: "yum install -y flex bison libxml2-devel zlib-devel cairo-devel && pip install -U cmake pip wheel && python setup.py build_c_core"
+          CIBW_BEFORE_BUILD: "yum install -y flex bison libxml2-devel zlib-devel cairo-devel && pip install -U cmake pip setuptools wheel && python setup.py build_c_core"
           CIBW_ARCHS_LINUX: aarch64
           CIBW_BUILD: "*-manylinux_aarch64"
 
@@ -91,7 +91,7 @@ jobs:
       - name: Build wheels (musllinux)
         uses: pypa/cibuildwheel@v2.17.0
         env:
-          CIBW_BEFORE_BUILD: "apk add flex bison libxml2-dev zlib-dev cairo-dev && pip install -U cmake pip wheel && python setup.py build_c_core"
+          CIBW_BEFORE_BUILD: "apk add flex bison libxml2-dev zlib-dev cairo-dev && pip install -U cmake pip setuptools wheel && python setup.py build_c_core"
           CIBW_ARCHS_LINUX: aarch64
           CIBW_BUILD: "*-musllinux_aarch64"
           CIBW_TEST_COMMAND: "cd {project} && pip install --prefer-binary '.[test-musl]' && python -m pytest -v tests"