chore: Ensure only current file is run with VSCode debugger

[eps1lon]

Without this change having open e.g. src/react/hoc/__tests__/mutations/queries.test.tsx running "Jest Current File" from VSCode's "Run and Debug" would result in /usr/bin/node ./node_modules/.bin/jest queries.test --config ./config/jest.config.js. However, this would match multiple files (here src/react/hoc/__tests__/mutations/recycled-queries.test.tsx and src/react/hoc/__tests__/mutations/queries.test.tsx.

With this change we ensure that only a single file is run.

Checklist:

• If this PR is a new feature, please reference an issue where a consensus about the design was reached (not necessary for small changes)
• Make sure all of the significant new logic is covered by tests

[apollo-cla]

@eps1lon: Thank you for submitting a pull request! Before we can merge it, you'll need to sign the Apollo Contributor License Agreement here: https://contribute.apollographql.com/

[benjamn]

Makes sense—thanks for improving this configuration @eps1lon!