allow bucket import to be idempotent

[harshavardhana]

Community Contribution License

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contributions to the project maintainers under the Apache 2 license.

Description

allow bucket import to be idempotent

Motivation and Context

do not need to be defensive in our approach,
we should override anything and everything
in the import process, do not care about what
currently exists on the disk - backup is the
source of truth.

How to test this PR?

Create an inconsistent state() on .metadata.bin and
Then, we try to restore, but we miserably fail.

We must not fail at any cost, unless of course we couldn't
save the damn file.

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Optimization (provides speedup with no functional changes)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

• Fixes a regression (If yes, please add commit-id or PR # here)
• Unit tests added/updated
• Internal documentation updated
• Create a documentation update request here