Fixed blankspace padding in char datatype for multibyte characters

[rohit01010]

Description

Currently when multi-byte character is casted to char(1) space padding was not done properly. This PR will fix this issue.

Tested locally

-- with server collation name = japanese_ci_as
1> select CONCAT(CAST('£' as char(1)), '|')
2> go
concat                                                                                                                                                                                                                                                          
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
 |                                                                                                                                                                                                                                                              

(1 rows affected)

-- with server collation name = chinese_prc_ci_as
1> select CONCAT(CAST('ち' AS char(1)),'|');
2> go
concat                                                                                                                                                                                                                                                          
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
 |                                                                                                                                                                                                                                                              

(1 rows affected)

Cherry-picked from: PR-2167
Signed-off-by: Rohit Bhagat [email protected]

Issues Resolved

BABEL-4638

Test Scenarios Covered

• Use case based - YES

• Boundary conditions - NA

• Arbitrary inputs - NA

• Negative test cases - NA

• Minor version upgrade tests - NA

• Major version upgrade tests - NA

• Performance tests - NA

• Tooling impact - NA

• Client tests - NA

Check List

• Commits are signed per the DCO using --signoff

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[rohit01010]

Already cherry-picked in BABEL_4_X_DEV along with other commits.