Replace confused emoji with slightly frowning face in quick reactions

[jeremiah-k]

Replace 😕 (confused face) with 🙁 (slightly frowning face) in the quick reaction menu to better represent mild disappointment rather than confusion about the message content. At a glance they look similar, but when hovering over/reading the reaction's description in Element Desktop (and possibly other clients), it can send the wrong message.

Pull Request Checklist

• [X ] I read the contributing guide
• UI change has been tested on both light and dark themes, in portrait and landscape orientations and on iPhone and iPad simulators
• [ X] Accessibility has been taken into account.

• [ X] Pull request is based on the develop branch

• [ X] Pull request contains a changelog file in ./changelog.d
• [ X] You've made a self review of your PR
• Pull request includes screenshots or videos of UI changes
• [ X] Pull request includes a sign off

Edit: After opening this PR, I checked the quick reactions across Element clients and found that Element iOS and Element Android currently use identical reaction sets, both including the confused face emoji, so this change would be good for Element Android as well.

The newer Element X clients use different approaches - Element X iOS uses a smaller base set (["👍️", "👎️", "🎉", "❤️"]) plus frequently used emojis, while Element X Android uses a different preset entirely (["👍️", "👎️", "🔥", "❤️", "👏"]). In both Element X clients, the confused face emoji isn't present.

I understand that Element X is the focus going forward and I'm not sure if there are plans to use matching emoji sets in the future, but as far as the legacy apps, many users are still actively using Element iOS (and Android) and would benefit from this UX improvement.

[CLAassistant]

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