Use all pips, no conda; add cache

Author: bact

.github/workflows/unittest-macos.yml

@@ -29,6 +29,7 @@ jobs:
       uses: actions/setup-python@v5
       with:
         python-version: ${{ matrix.python-version }}
+        cache: "pip"
     - name: Print system info
       run: sw_vers; python --version; arch
     - name: Install build tools

.github/workflows/unittest-windows.yml

@@ -26,16 +26,10 @@ jobs:
     - name: Checkout
       uses: actions/checkout@v4
     - name: Set up Python ${{ matrix.python-version }}
-      uses: conda-incubator/setup-miniconda@v3
+      uses: actions/setup-python@v5
       with:
         python-version: ${{ matrix.python-version }}
-        auto-activate-base: true
-        auto-update-conda: true
-    - name: Show environment
-      shell: powershell
-      run: |
-        conda info
-        conda list
+        cache: "pip"
     - name: Install build tools
       shell: powershell
       run: |

.github/workflows/unitttest-ubuntu.yml

@@ -29,6 +29,7 @@ jobs:
       uses: actions/setup-python@v5
       with:
         python-version: ${{ matrix.python-version }}
+        cache: "pip"
     - name: Install build tools
       run: |
         python -m pip install --upgrade "pip<24.1" "setuptools==73.0.1"