[Astro] Add `unstable_sentryVitePluginOptions`

[s1gr1d]

Description

Add unstable_sentryVitePluginOptions to allow passing all plugin options.

This is for example needed for things like passing the applicationKey for the thirdPartyErrorFilterIntegration (docs here).

[github-actions]

A PR closing this issue has just been released 🚀

This issue was referenced by PR #15638, which was included in the 9.6.0 release.