babelfish_extensions Add support for windows roles in T-SQL IS

Description

This commits adds support in T-SQL IS_MEMBER() function to show membership information for windows roles. The re-implemented IS_MEMBER() function relies on views sys.login_token and sys.user_token to see if current session user is member of a given role. The sys.user_token view has also been modified as part of this commit to show all the roles current_user is member of.

Task: BABEL-4822 Signed-off-by: Sharu Goel [email protected]

Test Scenarios Covered

Use case based - Yes
Boundary conditions - N/A
Arbitrary inputs - N/A
Negative test cases - N/A
Minor version upgrade tests - N/A
Major version upgrade tests - N/A
Performance tests - N/A
Tooling impact - N/A
Client tests - N/A

Check List

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