fix: internally wrap store subscribe in untrack

[trueadm]

Closes #13840. This issue keeps coming up time and time again. I think we can make the process of migration smoother by just internally wrapping the subscribe function in an untrack internally – which is what people would have had to have done in their functions anyway.

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[dummdidumm]

This issue keeps coming up time and time again

Where-else did it come up?
FWIW I think it makes sense because of the start-stop-notifier logic.

[trueadm]

Where-else did it come up?

It's come up a bunch on Discord and there's been a discussion thread about this too. I guess it's quite common to do because like you say people probably use start-stop-notifier logic or some equivalent of it in their custom store logic.