chore: update rustls-webpki 0.103.10 → 0.103.12

[janechu]

Description

Update rustls-webpki from 0.103.10 to 0.103.12 to resolve two security advisories that are failing the cargo deny lint gate:

• RUSTSEC-2026-0098: Name constraints for URI names were incorrectly accepted
• RUSTSEC-2026-0099: Name constraints were accepted for certificates asserting a wildcard name

This vulnerability on main is also causing lint failures on these open PRs:

• fix: apply type coercion for equality and not-equals comparisons #241
• fix: use quote-aware tag close detection in FAST parser plugin #242
• fix: preserve text content with bindings after void elements #243

Test Plan

• cargo deny check passes cleanly after the update
• No code changes, only Cargo.lock version bump

Checklist

• I have added tests for my changes.
• I have tested my changes.
• I have updated the project documentation to reflect my changes.
• I understand and have considered the performance impact of my changes.