rlqs: address nits from PR #37797

[bsurber]

Commit Message:

• Nit 1: Lambda capture for the RLQS filter factory callback should move shared_ptrs instead of copying. This only saves a shared_ptr copy op per var but is still good practice.
• Nit 2: Replace instances of if-conditions (!ptr) / (ptr) with (ptr == nullptr) / (ptr != nullptr) to conform to existing code.

Risk Level: minimal
Testing: unit testing
Docs Changes:
Release Notes:
Platform Specific Features:
Fixes commit #37797

[repokitteh-read-only]

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🐱

Caused by: #37851 was opened by bsurber.

see: more, trace.

[tyxia]

LGTM Thank you!