No way to rerun only errored unit tests #1657

Environment data

• VS Code version: 1.23.0
• Extension version (available under the Extensions sidebar): 2018.4.0
• OS and version: rhel 7
• Python version (& distribution if applicable, e.g. Anaconda): anaconda 3 in a python 2.7 env
• Type of virtual environment used (N/A | venv | virtualenv | conda | ...): conda
• Relevant/affected Python packages and their versions: pytest

Actual behavior

Run failed unit tests does not acknowledge erroring tests as failing

Expected behavior

either another option to run specifically errored tests, or rerun failed tests should also run errored tests (preferably the latter

Steps to reproduce:

1. make a subset of unit tests that get marked as errors in the test output
2. click 'rerun failed tests'