[CI] Run python unittests on OS X with Github Actions (#17771)

* Remove travis and appveyor config

* Update CODEOWNERS

* Run python unittests after build

.github/workflows/os_x_staticbuild.yml

@@ -16,3 +16,11 @@ jobs:
           git --version
           clang --version
           CMAKE_STATICBUILD=1 ./tools/staticbuild/build.sh cpu
+      - name: Setup Python
+        run: |
+          python3 -m pip install --user nose nose-timer nose-exclude numpy scipy
+          python3 -m pip install --user -e python
+      - name: Test project
+        run: |
+          python3 -m nose --with-timer --verbose tests/python/unittest/ --exclude-test=test_extensions.test_subgraph --exclude-test=test_extensions.test_custom_op --exclude-test=test_gluon_data.test_recordimage_dataset_with_data_loader_multiworker
+          

CODEOWNERS

@@ -42,8 +42,8 @@
 /plugin/          @pllarroy
 
 # Build system
-CMakeLists.txt    @szha @pllarroy
-/cmake/           @szha @pllarroy
+CMakeLists.txt    @szha @pllarroy @leezu
+/cmake/           @szha @pllarroy @leezu
 /make/            @szha
 
 # MXNet CI
@@ -53,8 +53,6 @@ dev_menu.py         @pllarroy
 /docker/            @marcoabreu
 /tests/ci_build/    @marcoabreu
 Jenkinsfile         @marcoabreu
-.travis.yml         @marcoabreu
-appveyor.yml        @marcoabreu
 
 # MXNet CD
 /cd/                @szha
@@ -75,5 +73,5 @@ prepare_mkl.sh    @szha
 # Tools
 /tools/           @szha @pllarroy
 
-# Github templates
-/.github/         @szha
+# Github configuration
+/.github/         @szha @leezu