Update install env for various GitHub workflow tests and ray, tensorf…

…low versions

.github/workflows/gh-test.yml

@@ -24,9 +24,9 @@ jobs:
       run: |
         python -m pip install --upgrade pip
         pip install flake8 pytest pytest-cov setuptools numpy
-        pip install -e .[extras_disc]
-        pip install ray[rllib,debug]==0.7.3
-        pip install tensorflow==1.13.1
+        pip install -e .[extras]
+        pip install ray[rllib,debug]
+        pip install tensorflow
     - name: Lint with flake8
       run: |
         # stop the build if there are Python syntax errors or undefined names