[bugfix] fix poll total vote double count

[Sentynel]

Description

In the case where the requesting user had voted in a poll, we would double count their votes towards the overall count of votes. This happens because we calculate a vote count of our own votes in case we can't see all the votes, but this isn't cleared before processing in the case where we can see all the votes, resulting in a double count.

closes #2463

Checklist

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[NyaaaWhatsUpDoc]

oh eagle eye! nice catch!