fix: refine regex used to identify asset links

[dcshzj]

Problem

The regex used to identify asset links is too general, which can give false positives when the root folder's permalink is just numbers.

Solution

Breaking Changes

• Yes - this PR contains breaking changes
• No - this PR is backwards compatible

Bug Fixes:

• Properly detect asset links by including the UUID v4 portion as part of the asset links regex.

Tests

• Go to Studio and create a root level folder with just numbers in the permalink (e.g. 2024)
• Create a page within this new folder using any name/permalink and save.
• Inside a separate page, create a link to this newly created page and publish.
• Verify that the link is indeed pointing to the newly created page from the second page that you edited.

[datadog-opengovsg]

Datadog Report

Branch report: fix/refine-asset-regex
Commit report: 9d0d133
Test service: isomer-studio

✅ 0 Failed, 266 Passed, 36 Skipped, 45.53s Total Time
⬆️ Test Sessions change in coverage: 1 increased (+1.59%)