use miniforge

Author: Tieqiong

Diff for: .github/workflows/matrix-and-codecov-on-merge-to-main.yml

@@ -32,7 +32,7 @@ jobs:
         uses: conda-incubator/setup-miniconda@v3
         with:
           activate-environment: test
-          auto-update-conda: true
+          miniforge-version: latest
           environment-file: environment.yml
           auto-activate-base: false
           python-version: ${{ matrix.python-version }}
@@ -44,9 +44,6 @@ jobs:
 
       - name: Install diffpy.pdfgui and requirements
         run: |
-          if [[ "${{ matrix.os }}" == "macos-13" ]]; then
-            export CONDA_OVERRIDE_OSX=11.0 # Override virtual package detection for osx-64
-          fi
           conda install --file requirements/test.txt
           conda install wxpython diffpy.utils matplotlib-base
           pip install diffpy.pdffit2==1.5.0rc1