Performance Improvement of create login in BBF

[anju15bharti]

Description

Engine PR : babelfish-for-postgresql/postgresql_modified_for_babelfish#507

In Major version 16 Babelfish introduced a new role bbf_admin_role which is a member of all the roles which created implicitly from TSQL. This increases the Load on any Grant/Revoke operations that happen since in BBF to "select the role through which it gets permission to current user to grant", is inefficient and loops over members of members to find the all members of the role even though the required role is find.
This commit optimizes the selection of role with is_admin_option true for babelfish by escaping the search for any TSQL roles conditionally.
Without the changes the time taken to create a login increases drastically and linearly:

Flame graph :

The average time consumed by create login stmt(with 125 dbs and 125 logins present) : 12836 ms
with these changes we see the time taken to create login increasing linearly but not as drastically as it was before the changes:

Flame graph :

The average time consumed by create login stmt(with 125 dbs and 125 logins present) : 49 ms

Check List

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[coveralls]

Pull Request Test Coverage Report for Build 12581937147

Details

• 13 of 16 (81.25%) changed or added relevant lines in 2 files are covered.
• 2 unchanged lines in 1 file lost coverage.
• Overall coverage increased (+0.002%) to 74.867%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
contrib/babelfishpg_tsql/src/hooks.c	2	3	66.67%
contrib/babelfishpg_tsql/src/catalog.c	11	13	84.62%

Files with Coverage Reduction	New Missed Lines	%
contrib/babelfishpg_tds/src/backend/tds/tdscomm.c	2	76.03%

Totals
Change from base Build 12556954627:	0.002%
Covered Lines:	46612
Relevant Lines:	62260

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💛 - Coveralls

[tanscorpio7]

let us also merge this fix in 17.2 & 16.7. This will help us skip creating before and after files for this test case.

[anju15bharti]

We will still need to create before file for version before 16.7 as it was failing for 16.1 and some other versions as well.
This commit can be cherry-picked into 16.7 and 17.2 branch as well.

[surendravishnoi]

let us not assume that memlist will be non-null, we should check for it and fallback to PG in case of null

[anju15bharti]

SearchCatCacheList inside SearchSysCacheList2 ensures that memlist value should not be null as it allocates memory to memlist even if no entry matches in the search and assign memlist->n_members as 0.
And when memlist->n_members will be 0, this API will return false falling back to PG API.