MSSQL sample-data query fix

[ayush-shah]

Describe your changes :

fix #361
Limit doesn't work in MSSQL, had to override the method to use Top
Changed the pointing of different metadata sinks to one sink (metadata-rest)
Added custom query format support to override the default query format

Type of change :

• Bug fix

Checklist:

• I have read the CONTRIBUTING document.
• I have performed a self-review of my own.
• I have tagged my reviewers below.
• I have commented on my code, particularly in hard-to-understand areas.
• My changes generate no new warnings.
• I have added tests that prove my fix is effective or that my feature works.
• All new and existing tests passed.

Reviewers

@harshach