Don't accidentally mix DTO and non-DTO types in query-history-store.test.ts

[robertbrignull]

I hit some errors in https://github.com/github/vscode-codeql/actions/runs/7695850568/job/20969605471?pr=3287 and this made me realise that query-history-store.test.ts is being a bit naughty when writing test data. We're writing the query history file but the data being written is the internal query history types instead of the query history DTO types.

This PR introduces a writeRawQueryHistory method which accepts the correct QueryHistoryDto type and writes it to disk. Hopefully this will help avoid people making the same mistake in the future by discouraging direct use of writeFileSync and writing incorrect JSON.

When I merge this branch into the robertbrignull/move_language_pack branch then the no-workspace tests pass locally (where they don't before) so that convinces me this change is correct.

Checklist

• CHANGELOG.md has been updated to incorporate all user visible changes made by this pull request.
• Issues have been created for any UI or other user-facing changes made by this pull request.
• [Maintainers only] If this pull request makes user-facing changes that require documentation changes, open a corresponding docs pull request in the github/codeql repo and add the ready-for-doc-review label there.

[charisk]

Thanks for tidying that up!