### What does this PR do?
fixes an issue where fetch requests with `Content-Type:
application/x-www-form-urlencoded` would not include the request body in
curl logs when `BUN_CONFIG_VERBOSE_FETCH=curl` is enabled
previously, only JSON and text-based content types were recognized as
safe-to-print in the curl formatter. This change updates the allow-list
to also handle `application/x-www-form-urlencoded`, ensuring bodies for
common form submissions are shown in logs
### How did you verify your code works?
- added `Content-Type: application/x-www-form-urlencoded` to a fetch
request and confirmed that `BUN_CONFIG_VERBOSE_FETCH=curl` now outputs a
`--data-raw` section with the encoded body
- verified the fix against the reproduction script provided in issue
#12042
- created and ran a regression test
- checked that existing content types (JSON, text, etc.) continue to
print correctly
fixes#12042
