Add macos CI runner

Author: kislyuk

.github/workflows/ci.yml

@@ -4,7 +4,7 @@ on: [push]
 
 jobs:
   run_unit_tests:
-    runs-on: ubuntu-18.04
+    runs-on: [ubuntu-18.04, ubuntu-20.04, macos-10.15]
     strategy:
       max-parallel: 8
       matrix:
@@ -17,7 +17,7 @@ jobs:
         python-version: ${{ matrix.python-version }}
     - name: Install
       run: |
-        sudo apt-get install jq
+        [[ $(uname) == Linux ]] && sudo apt-get install --no-install-recommends python3-openssl python3-lxml
         pip install coverage wheel
         make install
     - name: Test