message: Fix 'envFile' launch.json option on Windows
  The 'workspaceFolder' subsitution logic was wrong for 'envFile', which broke the feature on Windows. This fixes it.
diff: @@ -137,7 +137,7 @@ export class CSharpConfigurationProvider implements vscode.DebugConfigurationPro
  // read from envFile and set config.env
  if (config.envFile) {
  - config = this.parseEnvFile(config.envFile.replace(/\${workspaceFolder}/g, folder.uri.path), config);
  + config = this.parseEnvFile(config.envFile.replace(/\${workspaceFolder}/g, folder.uri.fsPath), config);
  }
  // vsdbg will error check the debug configuration fields
  