CI: split workflows

[wkpark]

split cmake workflows into several jobs, based on #949, #947 @rickardp and @akx's work.

• split build job into shared-libs, shared-cuda, wheels jobs.
• add ubuntu aarch64 build.
• reduce environment-bnb.yml package dependency to reduce build time.

[github-actions]

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[Titus-von-Koeller]

Thanks very much @wkpark! yes, makes sense to split it out.