Fix multimodal textbox placeholder

[dawoodkhan82]

Description

Fixes placeholder spacing when submit is clicked.

Closes: #(issue)

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[gradio-pr-bot]

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Install Gradio from this PR

pip install https://gradio-builds.s3.amazonaws.com/d8164a21eb1bc7dd332549c16dfd72aa553eb499/gradio-4.32.2-py3-none-any.whl

Install Gradio Python Client from this PR

pip install "gradio-client @ git+https://github.com/gradio-app/gradio@d8164a21eb1bc7dd332549c16dfd72aa553eb499#subdirectory=client/python"

Install Gradio JS Client from this PR

npm install https://gradio-builds.s3.amazonaws.com/d8164a21eb1bc7dd332549c16dfd72aa553eb499/gradio-client-0.20.1.tgz

[gradio-pr-bot]

🦄 change detected

This Pull Request includes changes to the following packages.

Package	Version
@gradio/multimodaltextbox	patch
gradio	patch

• [ ] Maintainers can select this checkbox to manually select packages to update.

With the following changelog entry.

Fix multimodal textbox placeholder

Maintainers or the PR author can modify the PR title to modify this entry.

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[abidlabs]

This fixes the issue in the default Gradio theme, but it seems that now the positioning of the multimodal textbox icons in the other themes is off again, reverting the fixes in: https://github.com/gradio-app/gradio/pull/8369. E.g. monochrome:

Can you confirm that a standard gr.ChatInterface(multimodal=True) works with all 5 of the built-in themes?

import gradio as gr

gr.ChatInterface(lambda x,y:x["text"], multimodal=True, theme="monochrome").launch()

[abidlabs]

I'm going to auto-merge this so that @aliabid94 can do a release if needed