feat: vote_update event (#2596)

* Merge branch 'add-polls' into polls-ext

* added listener to poll votes

* added isUnvote property

* added option for custom message secret

* usage example updated

* added logic for catching removed votes

* usage example updated

* fixed logic for poll vote events

* temp usage example

* No more `isCurrentState`

* messageSecret converted to array

Co-authored-by: tuyuribr <45042245+tuyuribr@users.noreply.github.com>

* docs updated

* we already have messageSecret in vote.parentMessage

* PollVote.selectedOptions changed to be similar to pollOptions

* docs fixed

* window.injectToFunction clarifications

* minor clarifications

* fix: typo

* style: fix broken link in readme file

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Co-authored-by: tuyuribr <45042245+tuyuribr@users.noreply.github.com>

src/structures/index.js

@@ -20,4 +20,5 @@ module.exports = {
     Payment: require('./Payment'),
     Reaction: require('./Reaction'),
     Poll: require('./Poll'),
+    PollVote: require('./PollVote')
 };