Fixes new line issue in chatbot

[dawoodkhan82]

Description

Adds margin between <p> tags

Please include:

• relevant motivation
• a summary of the change
• which issue is fixed.
• any additional dependencies that are required for this change.

Closes: #4344

Checklist:

• I have performed a self-review of my own code
• I have added a short summary of my change to the CHANGELOG.md
• My code follows the style guidelines of this project
• I have commented my code in hard-to-understand areas
• I have made corresponding changes to the documentation
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes

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[gradio-pr-bot]

All the demos for this PR have been deployed at https://huggingface.co/spaces/gradio-pr-deploys/pr-4491-all-demos

[abidlabs]

Perfect! Tested with

import gradio as gr

message = [(
    "Single newline:\nMessage continues here",
    "Double newline:\n\nMessage continues here",    
),(
    "Triple newline:\n\n\nMessage continues here",    
    "Quadruple newline:\n\n\n\nMessage continues here",        
)]

with gr.Blocks() as demo:
    gr.Chatbot(message)
    
demo.launch()

And behaves the same as GFM!

[abidlabs]

By the way, as I was testing the gr.Chatbot, I noticed something else that seems to be broken on main. Any codeblocks seem to have huge vertical padding on top. For example:

import gradio as gr

code = """
```python
def greet(x):
    return "hello, " + x
```
"""

message = [(
    "write a python program",
    code
)]

with gr.Blocks() as demo:
    gr.Chatbot(message)
    
demo.launch()

produces this:

This is broken on main, not from this PR, but if it's easier, perhaps you can fix in this PR as well? It's not broken on pypi from what I can tell.

[dawoodkhan82]

@abidlabs seems like its an issue with the copy button that was added. Will fix in this pr

[dawoodkhan82]

will address copy button issue in new pr.