Fix namespace for string functions in system views/functions

[Anikait143]

Description

1. Issues

• As an effort to fix string functions, we introduced various function definitions is sys schema, but there are a few places where we overlooked to prepend PG_CATALOG in the function calls inside system view/functions which may cause mVU/MVU failures due to error while executing upgrade scripts due to invalid argument type.
• Affected functions were - RTRIM, STRING_AGG, SUBSTRING, LOWER.

2. Changes made to fix the issues

• Prepended appropriate namespace at suitable function calls as a proactive measure to prevent m/MVU failures, Since, invalid datatypes for sys function definitions which can cause issue will now be redirected to pg_catalog function definitions and will work correctly as before.

Task: BABEL- 5362 Authored-by: Anikait Agrawal agraani@amazon.com Signed-off-by: Anikait Agrawal agraani@amazon.com

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 -

• Memory tests -

• Client tests -

Check List

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

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[coveralls]

Pull Request Test Coverage Report for Build 11964419447

Details

• 0 of 0 changed or added relevant lines in 0 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage remained the same at 74.654%

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Totals
Change from base Build 11954537654:	0.0%
Covered Lines:	46024
Relevant Lines:	61650

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💛 - Coveralls