Fix: close browser after URL processing with Playwright

[edamame8888]

*Issue #341

Description of changes:

This pull request enhances the resource management of our URL loading function by ensuring that Playwright pages are closed after processing each URL. It incorporates a page.close() statement within the URL processing loop and closes the browser with browser.close() at the end of the session. These changes prevent resource leaks and improve performance during bulk URL operations.

Changes:

• Inserted page.close() within the loop to close each page after its content is processed. a8379fb94ed974e45f2fb2d2f63319c9cbe1c5e8

[edamame8888]

Performance Before & After

The memory being maxed out at 100% is the cause.

Before the improvement, the memory performance in Cloud Watch Insight was maxed out and the content retrieval never finished. After the improvement, memory performance improved and we confirmed that the embedding was completed in a short period of time.

https://github.com/aws-samples/bedrock-claude-chat/issues/341#issuecomment-2151090410

[statefb]

Thank you for the investigation with clear evidence! LGTM, thank you for your contribution!! @edamame8888

[statefb]

Merged v1 by #346