Restrict DROP USER/ROLE from non-dbo user

[anju15bharti]

Description

Cherry Picked From 2859 and 2863

Earlier, any user was able to drop user/role, irrespective of whether that user has required privileges or not.

With this commit, only dbo should have the permission to drop user/role.

Issues Resolved

BABEL-5173

Test Scenarios Covered

• Use case based -

• Boundary conditions -

• Arbitrary inputs -

• Negative test cases -

• Minor version upgrade tests -

• Major version upgrade tests -

• Performance tests -

• Tooling impact -

• Client tests -

Check List

• [ ] Commits are signed per the DCO using --signoff

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[coveralls]

Pull Request Test Coverage Report for Build 10555173997

Details

• 19 of 19 (100.0%) changed or added relevant lines in 1 file are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+0.01%) to 73.697%

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Totals
Change from base Build 10472203668:	0.01%
Covered Lines:	44219
Relevant Lines:	60001

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💛 - Coveralls