Fix chat

[MatthiasReumann]

Motivation and Context

In #1135 the textarea tag hasn't been closed. As a result the chat UI doesn't work properly. Furthermore, it broke the polls. (For examples, see testserver of #1145)

Description

Close tag.

Steps for Testing

Prerequisites:

• 1 Account
• 1 Livestream

1. Log in
2. Navigate to a Livestream
3. Chat send button should say send and not New Poll.
4. Polls work.
5. 🤠

[github-actions[bot]]

Your Testserver will be ready at https://1147.test.live.mm.rbg.tum.de in a few minutes.

Logins

| Kurs1 | Kurs2 | Kurs3 | Kurs4 | | ---------------------------------------- | ------------------------- | ------------------------- | ------------------------- | | public | public | loggedin | enrolled | | prof1 | prof1 | prof2 | prof1
prof2 | | student1
student2
student3 | student1
student2 | student2
student3 | student1
student2 |