Merge pull request #166 from kejacobson/fix_ci_build_docs

Fix pip install for mphys in build_docs github actions

.github/workflows/host_docs.yml

@@ -51,7 +51,7 @@ jobs:
           cd OpenMDAO;
           pip install .[all];
           cd ../mphys;
-          pip install -e .
+          pip install -e .[all];
           echo "=============================================================";
           echo "List installed packages/versions";
           echo "=============================================================";