Deprecate `donjayamanne.python-environment-manager`

source: https://open-vsx.org/extension/donjayamanne/python-environment-manager

```json
"donjayamanne.python-environment-manager": {
"disallowInstall": false,
"extension": {
"id": "ms-python.vscode-python-envs",
"displayName": "Python Environments"
}
}
```

Start by locating the publishing configuration containing the extension ID `donjayamanne.python-environment-manager`, then compare it with the Open VSX source entry and the supplied replacement metadata. Done means the old extension is configured as deprecated or disallowed for installation and the `ms-python.vscode-python-envs` replacement details match the issue.

Written by the indexing model from the issue text.