Use markRaw() to signal non reactive data in store

[rak-phillip]

Summary

This utilizes markRaw() to ensure that certain properties in the Vuex store are marked as "non-reactive".

Fixes #11098

Technical notes summary

Upon further review of #11062, I thought that Object.defineProperty() was being used, in part, to mark certain properties as "non-reactive" in the Dashboard store. $plugin, $router, & $route really don't need reactivity associated with them.

We might want to consider following up in the future to decide if any of these properties belong in the Vuex store at all. We can achieve a similar result by utilizing a singleton or some similar pattern that will allow us to share these definitions throughout Dashboard.

Areas or cases that should be tested

Anything that accesses the $router, $route, or $plugin states stored in the store.

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