feat: Introduce new ObjectExistsWithSize API to

[DylanGuedes]

What this PR does / why we need it:
Introduce a new ObjectExistsWithSize API to our object storage interface.
This is the same as ObjectExists but with the object size as part of the return value. This is useful to compare the object size present.

Which issue(s) this PR fixes:
Fixes #

Special notes for your reviewer:

Checklist

• Reviewed the CONTRIBUTING.md guide (required)
• Documentation added
• Tests updated
• Title matches the required conventional commits format, see here
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