[inspector-monitor] Add explicit return types

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🦋 Changeset detected

Latest commit: 2f01a276346574aac52989b0412658b508b700ed

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 2 packages

| Name | Type | | --------------------------------- | ----- | | @redux-devtools/inspector-monitor | Patch | | @redux-devtools/rtk-query-monitor | Patch |

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