Fix premature installation completion signal in Bloom installer. This CL removes calls to `status_reporter_.Complete(**true**, success_msg)` within the `VerifyBundleSignature` and `GetOwnerConfig` methods. These functions represent intermediate steps in the installation process, not its completion, so we shouldn't mark the installation process as complete. PiperOrigin-RevId: 930656122 Change-Id: Iafbbbb270d44ab73e1fe44b3312dce5d6eb81892