Fix the issue of duplicate counting of num_executed in gp_toolkit.gp_resgroup_status

[fairyfar]

What does this PR do?

Fix the issue of duplicate counting of num_executed in gp_toolkit.gp_resgroup_status
This is a defect of the original GPDB.
When enabling resource group management and the transaction switches from "Assigned" to "Bypass" state, the "num_executed" counter is repeatedly counted.

Reproducing test cases:

1. Enable resource group: set gp_resource_manager to "group".

2. Log in with the default superuser.

3. Execute gp_toolkit.gp_resgroup_status twice.

SELECT groupname, num_executed FROM gp_toolkit.gp_resgroup_status WHERE groupname='admin_group';
 groupname   | num_executed 
-------------+--------------
 admin_group | 31           
(1 row)
SELECT groupname, num_executed FROM gp_toolkit.gp_resgroup_status WHERE groupname='admin_group';
 groupname   | num_executed 
-------------+--------------
 admin_group | 33           
(1 row)

The test case has been added to:

‎src/test/isolation2/sql/resgroup/resgroup_bypass.sql

Type of Change

• Bug fix (non-breaking change)
• New feature (non-breaking change)
• Breaking change (fix or feature with breaking changes)
• Documentation update

Breaking Changes

Test Plan

• Unit tests added/updated
• Integration tests added/updated
• Passed make installcheck
• Passed make -C src/test installcheck-cbdb-parallel

Impact

Performance:

User-facing changes:

Dependencies:

Checklist

• Followed contribution guide
• Added/updated documentation
• Reviewed code for security implications
• Requested review from cloudberry committers

Additional Context

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