add a github action which will try and build all packages, all platforms

.github/workflows/build_packages.yml

@@ -0,0 +1,46 @@
+name: Build Packages
+
+concurrency:
+  group: ${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: true
+
+on:
+  pull_request:
+  workflow_dispatch:
+  push:
+    branches:
+      - stable
+jobs:
+  build:
+    strategy:
+      fail-fast: false
+      matrix:
+        os: [ubuntu-latest, macos-13, macos-latest, windows-latest]
+        recipe: [diffeqpy, pyrms, symmetry]
+    runs-on: ${{ matrix.os }}
+    defaults:
+      run:
+        shell: bash -l {0}
+    steps:
+      - uses: actions/checkout@v4
+      - name: Setup Conda
+        uses: conda-incubator/setup-miniconda@v3
+        with:
+          auto-update-conda: false
+          conda-solver: libmamba
+          auto-activate-base: true
+          activate-environment: ""
+      - name: Install Build Tools
+        run: conda install python anaconda-client conda-build
+      - name: Configure Auto-Upload
+        if: github.ref == 'refs/heads/stable'
+        run: |
+          conda config --set anaconda_upload yes
+      - name: Build Binary
+        run: |
+          # set a default value to the conda_token if needed (like from forks)
+          : "${CONDA_TOKEN:=${{ secrets.ANACONDA_TOKEN }}}"
+          : "${CONDA_TOKEN:=default_value}"
+          echo "CONDA_TOKEN=$CONDA_TOKEN" >> $GITHUB_ENV
+          conda config --add channels conda-forge rmg
+          conda build --token $CONDA_TOKEN --user rmg ${{ matrix.recipe }}