fix: Block person properties updates if ridiculously many

[tiina303]

Problem

https://posthog.slack.com/archives/C06KX72191N/p1708187393272559

Didn't add the UI side explanations yet

Note that once they fix their implementation problem they can do a $merge_dangerously into a different distinct_id (making sure to send an event first so the person merge happens), which would reset the version.

Changes

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How did you test this code?