Test lower limits of dependencies

.ci_support/environment-old.yml

@@ -0,0 +1,5 @@
+channels:
+  - conda-forge
+dependencies:
+  - pandas =1.5.3
+  - scandir =1.10.0

.github/workflows/unittests_old.yml

@@ -0,0 +1,33 @@
+# This workflow will install Python dependencies, run tests and lint with a variety of Python versions
+# For more information see: https://help.github.com/actions/language-and-framework-guides/using-python-with-github-actions
+
+name: Unittest Lower Bound
+
+on:
+  push:
+    branches: [ main ]
+  pull_request:
+    branches: [ main ]
+
+jobs:
+  build:
+
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v2
+    - uses: conda-incubator/setup-miniconda@v2.2.0
+      with:
+        python-version: '3.9'
+        mamba-version: "*"
+        channels: conda-forge
+        channel-priority: strict
+        auto-update-conda: true
+        environment-file: .ci_support/environment-old.yml
+        miniforge-variant: Mambaforge
+    - name: Setup
+      shell: bash -l {0}
+      run: |
+        pip install --no-deps .
+    - name: Test
+      shell: bash -l {0}
+      run: python -m unittest discover tests