ci: unify ci workflow

[Boshen]

Summary

This unifies all CI related tasks into one workflow. In addition:

• changed how pnpm cache is restored and saved, it is now only saved when necessary, on the main branch
• removed --release from cargo check to save some cache space, it's currently using 1.5G of cache, which is too much for the 10G limit.

Example Run: https://github.com/web-infra-dev/rspack/actions/runs/5086537787

🤖 Generated by Copilot at 390196a

This pull request updates the CI pipeline for the rspack project, using custom actions for caching and a new workflow file ci.yml that runs various checks and tests on different platforms. It also deletes some unused or redundant workflow files and adds a new input parameter save-if to the cache actions.

Walkthrough

🤖 Generated by Copilot at 390196a

• Add a new workflow file ci.yml that defines the main CI pipeline for the rspack project (link)
• Add a new input parameter save-if to the pnpm-cache and rust-cache actions that allows the user to specify a condition for saving the cache (link, link)
• Replace the actions/cache action with the actions/cache/restore and actions/cache/save actions in the pnpm-cache action (link, link)
• Delete the check-rs.yaml, common-check.yaml, and test.yml workflow files, as they are replaced by the ci.yml workflow (link, link, link)