Bump Silicon/Arm/MU_TIANO from db6a2b6 to d4b663f (#1281)

Bumps [Silicon/Arm/MU_TIANO](https://github.com/microsoft/mu_silicon_arm_tiano) from `db6a2b6` to `d4b663f`.
- [Release notes](https://github.com/microsoft/mu_silicon_arm_tiano/releases)
- [Commits](microsoft/mu_silicon_arm_tiano@db6a2b6...d4b663f)

---
updated-dependencies:
- dependency-name: Silicon/Arm/MU_TIANO
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <[email protected]>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>