Rollup merge of #135739 - wesleywiser:dwarf_version_handling, r=lqd

Clean up uses of the unstable `dwarf_version` option

- Consolidate calculation of the effective value.
- Check the target `DebuginfoKind` instead of using `is_like_msvc`.
- Add the tracking issue to the unstable book page for this feature.

cc #103057

Author: matthiaskrgr