Added BBF hook to truncate numeric result to correct scale

[rohit01010]

Description

Currently, whenever an arithmetic operation is performed which results in numeric/decimal, we are storing the result till maximum possible scale instead of the correct scale. This is causing incorrect results in some arithmetic operations such as numeric division, numeric multiplication etc. This PR will fix this issue by adding a hook in engine which truncates the result value to the correct scale.

Engine PR: babelfish-for-postgresql/postgresql_modified_for_babelfish#529
Cherry-picked from: #3455

Issues Resolved

BABEL-5467

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 13452609233

Details

• 142 of 178 (79.78%) changed or added relevant lines in 3 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+0.05%) to 75.034%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
contrib/babelfishpg_tsql/src/hooks.c	49	54	90.74%
contrib/babelfishpg_tds/src/backend/tds/tdsresponse.c	92	123	74.8%

Totals
Change from base Build 13414925493:	0.05%
Covered Lines:	47224
Relevant Lines:	62937

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💛 - Coveralls