fix(vscode): missing coverage on single } line

[alestiago]

Description

The coverage tooling used in the VS Code extension is failing to report coverage on a line with a single closing }.

Steps To Reproduce

1. Clone the repository.

2. Install the dependencies (from extensions/vscode):

npm i

3. Remove the start and stop ignore coverage comments in debug-dev-server.ts.

4. Run the test tool (from extensions/vscode):

npm test

5. Coverage is not reported for a line with a single closing }.

Expected Behavior

To report coverage on the line with a single closing }.

Additional Context

• See original comment https://github.com/VeryGoodOpenSource/dart_frog/pull/955#discussion_r1304578191

• Workflow failure