Fix/tech debt (#128)

* switch from m2r to m2r2

* update mac to latest

* add more dependencies for error

* trigger test workflow on forked pull request

* try with macos-13

Author: jdkent

.github/workflows/testing.yml

@@ -43,7 +43,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        os: ["ubuntu-latest", "macos-latest"]
+        os: ["ubuntu-latest", "macos-13"]
         python-version: ["3.8", "3.9", "3.10", "3.11"]
 
     name: ${{ matrix.os }} with Python ${{ matrix.python-version }}