Update snafu requirement from 0.7 to 0.8 in /object_store

Updates the requirements on [snafu](https://github.com/shepmaster/snafu) to permit the latest version.
- [Changelog](https://github.com/shepmaster/snafu/blob/main/CHANGELOG.md)
- [Commits](shepmaster/snafu@0.7.0...0.8.0)

---
updated-dependencies:
- dependency-name: snafu
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <support@github.com>

object_store/Cargo.toml

@@ -38,7 +38,7 @@ humantime = "2.1"
 itertools = "0.12.0"
 parking_lot = { version = "0.12" }
 percent-encoding = "2.1"
-snafu = "0.7"
+snafu = "0.8"
 tracing = { version = "0.1" }
 url = "2.2"
 walkdir = "2"