Update taffy to latest main - #751

Summary

Bump the pinned taffy git rev 7eddc45a → 02820e54 (latest main). Pulls in:

• Block: clamp and synthesize scroll-container baselines (Block: clamp and synthesize scroll-container baselines taffy#1126)
• Flexbox: generate container baseline from visually startmost line/item for reverse containers (Flexbox: fix container baseline for column-reverse containers taffy#1127)
• Grid: exclude items with auto block-axis margins from baseline alignment (Grid: exclude items with auto block-axis margins from baseline alignment taffy#1125)

No code changes required; cargo check --workspace and cargo test --workspace pass, and WPT results (css/CSS2, css-flexbox, css-grid) are unchanged vs the previous rev.

Link to Devin session: https://dioxus.staging.devinenterprise.com/sessions/e9fbc6900f2c469d84ca90d71a628d7b
Requested by: @nicoburns

WPT results

No changes in test results compared to main.

_{Generated by the WPT workflow.}