ci: cache the compare tests' ngtsc baseline with vp run - #711

Node.js 20 is deprecated. The following actions target Node.js 20 but are being forced to run on Node.js 24: Swatinem/rust-cache@fb003b4f771bbf9c2de31d5f65c40689cc097fb5. For more information see: https://github.blog/changelog/2025-09-19-deprecation-of-node-20-on-github-actions-runners/

Failed to save: <h2>Our services aren't available right now</h2><p>We're working to restore all services as soon as possible. Please check back soon.</p>0JE/0agAAAABLHoyK68sBRK8tkw0RH9CQUEhYMzFFREdFMDYxMgBFZGdl

Failed to restore: Cache service responded with 400