fix(lighthouse): ensure teardown runs when withPage throws

[Kikobeats]

Summary

• Wrap the withPage call in try/finally so the teardown callback always executes, preventing browser context leaks when lighthouse audits fail (timeouts, navigation errors, etc.)
• No changes needed in microlink/api — the existing teardown(() => browserless.close(id)) registration works correctly once the teardown is guaranteed to run

Context

When withPage() throws, the teardown callback registered by consumers (e.g. browserless.close(id) in microlink/api) was never called because control flow skipped the teardown line. This caused browser contexts to leak on every failed lighthouse audit.

Closes #693

Made with Cursor

---

Note

Low Risk
Low risk control-flow change that ensures teardown runs even when browserless.withPage throws, reducing the chance of leaked browser contexts.

Overview
Ensures browser resources are always cleaned up by wrapping the browserless.withPage(...)() call in try/finally and moving the teardown invocation into the finally block.

This guarantees teardown executes on Lighthouse failures/timeouts instead of being skipped on exceptions.

^{Reviewed by Cursor Bugbot for commit e653fb9. Bugbot is set up for automated code reviews on this repo. Configure here.}

[coveralls]

Coverage is 74.715% — fix/lighthouse-context-leak into master. No base build found for master.