remove unreachable null result check in GetBlobs

[SimonCropp]

Fixes #
Design discussion issue #

Changes

Please provide a brief description of the changes here.

Merge requirement checklist

• CONTRIBUTING guidelines followed (license requirements, nullable enabled, static analysis, etc.)
• Unit tests added/updated
• Appropriate CHANGELOG.md files updated for non-trivial changes
• Changes in public API reviewed (if applicable)

[Kielek]

Please update first https://github.com/open-telemetry/opentelemetry-dotnet-contrib/tree/89f0af731441a364779693a1874c57f33b1e721c/src/OpenTelemetry.PersistentStorage.Abstractions

Then we can resync packages

[SimonCropp]

@Kielek i dont understand

[Kielek]

You are trying to update PersistentBlobProvider. This class is borrowed from the conitrb repository. If you want to modify it, please do it in the contrib repo. Then we can propagate changes here.