vscode-python: the working directory is not set as expected for Pyramid debug config

Environment data

• VS Code version: 1.36
• Extension version (available under the Extensions sidebar): 2019.8.29288
• OS and version: macOS Mojave 10.14.6
• Python version (& distribution if applicable, e.g. Anaconda): 2.7.10
• Type of virtual environment used (N/A | venv | virtualenv | conda | …): virtualenv
• Relevant/affected Python packages and their versions: pyramid 1.5.8
• Jedi or Language Server? (i.e. what is "python.jediEnabled" set to; more info #3977): N/A

Expected behaviour

The Pyramid debug config runs with the working directory the same as the entry file. This happens, for example, if we set create the Pyramid debug config with "cwd":"${fileDirName}"

Actual behaviour

Pyramid debug config is created without cwd set and it appears to default to the parent directory, which causes my pyramid app to be unable to resolve static asset paths.

Steps to reproduce:

1. Debug > Add Configuration > Python > Pyramid