Fix missing monitors in subgroups due to missing filterFunc

[David-Development]

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Description

Fixes bug where monitors in subgroups are not visible due to the filterFunc not being passed on recursively.

Type of change

• Bug fix (non-breaking change which fixes an issue)

Checklist

• My code follows the style guidelines of this project
• I ran ESLint and other linters for modified files
• I have performed a self-review of my own code and tested it
• I have commented my code, particularly in hard-to-understand areas (including JSDoc for methods)
• My changes generates no new warnings
• My code needed automated testing. I have added them (this is optional task)

Screenshots (if any)

Before:

After:

[CommanderStorm]

LGTM

Normally, I would request to issue this against the 1.23.x branch, but if this is a V2 only fix, I am fine with it (primaryly because that release seems mostly done)