Expose plan checker router scheduler plugin counter Mbeans explicitly

[pdabre12]

Description

Expose plan checker router scheduler plugin counter Mbeans explicitly.

Motivation and Context

The java/ native redirect requests counters weren't exposed.

Impact

Users will be able to see the counters.

Test Plan

CI

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• Documented new properties (with its default value), SQL syntax, functions, or other functionality.
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• Adequate tests were added if applicable.
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Release Notes

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== NO RELEASE NOTE ==

[steveburnett]

LGTM! (docs)