chore(deps): bump @rspack/core in Faster from 1.2.0-alpha.0 to 1.2.2

[tats-u]

Pre-flight checklist

• I have read the Contributing Guidelines on pull requests.
• If this is a code change: I have written unit tests and/or added dogfooding pages to fully verify the new behavior.
• If this is a new API or substantial change: the PR has an accompanying issue (closes #0000) and the maintainers have approved on my working plan.

Motivation

According to #10823 (comment), the change planned in Rspack 1.2.3 increases the chance of enablement of the persistent cache in Docusaurus Faster powered. That in the current Rspack version is incompatible especially with assets of imported images.
However, Docusaurus Faster still pins Rspack to the unstable 1.2.0-alpha.0 today even though 1.2.2 has been released. This PR makes Docusaurus Faster accept stable Rspack versions including 1.2.3 or later.

Test Plan

Everything works as usual without any regressions even when Faster is enabled.

Configurations without Faster are not affected by this PR.

Test links

Deploy preview: https://deploy-preview-_____--docusaurus-2.netlify.app/

Related issues/PRs

#10823

[netlify]

✅ [V2]

Built without sensitive environment variables

Name	Link
🔨 Latest commit	5318b1f
🔍 Latest deploy log	https://app.netlify.com/sites/docusaurus-2/deploys/67976cff8c4544000829e948
😎 Deploy Preview	https://deploy-preview-10870--docusaurus-2.netlify.app
📱 Preview on mobile	Toggle QR Code... Use your smartphone camera to open QR code link.

---

To edit notification comments on pull requests, go to your Netlify site configuration.

[github-actions]

⚡️ Lighthouse report for the deploy preview of this PR

URL	Performance	Accessibility	Best Practices	SEO	Report
/	🔴 46	🟢 98	🟢 96	🟢 100	Report
/docs/installation	🔴 49	🟢 97	🟢 100	🟢 100	Report
/docs/category/getting-started	🟠 72	🟢 100	🟢 100	🟠 86	Report
/blog	🟠 61	🟢 96	🟢 100	🟠 86	Report
/blog/preparing-your-site-for-docusaurus-v3	🟠 64	🟢 92	🟢 100	🟢 100	Report
/blog/tags/release	🟠 64	🟢 96	🟢 100	🟠 86	Report
/blog/tags	🟠 74	🟢 100	🟢 100	🟠 86	Report

[slorber]

Thanks, was going to do that 👍