Adds a filterable parameter to gr.Dropdown that controls whether user can type to filter choices

[abidlabs]

Closes: #5465

Example code:

import gradio as gr

def printy(x):
    print(x)
    return x

with gr.Blocks() as demo:
    gr.Markdown("Inputs")
    d1 = gr.Dropdown(["choice 1", ("choice 2 [with value]", "value 2"), "choice 3"], label="single select", filterable=False,
                    multiselect=False)
    d2 = gr.Dropdown(["choice 1", ("choice 2 [with value]", "value 2"), "choice 3"], label="multi select", filterable=False,
                    multiselect=True, max_choices=2)
    d3 = gr.Dropdown(["choice 1", ("choice 2 [with value]", "value 2"), "choice 3"], label="single select allow_custom_value",
                    multiselect=False, allow_custom_value=True)
    d4 = gr.Dropdown(["choice 1", ("choice 2 [with value]", "value 2"), "choice 3"], label="multi select allow_custom_value",
                    multiselect=True, max_choices=2, allow_custom_value=True)
    
    gr.Markdown("Outputs")
    t = gr.Textbox()
    
    d1.change(printy, d1, t)
    d2.change(printy, d2, t)
    d3.change(printy, d3, t)
    d4.change(printy, d4, t)
    
demo.launch()

[gradio-pr-bot]

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---

Install Gradio from this PR

pip install https://gradio-builds.s3.amazonaws.com/4a50a9e1831f800b999aae4fbfd23a35c930a585/gradio-3.43.2-py3-none-any.whl

Install Gradio Python Client from this PR

pip install "gradio-client @ git+https://github.com/gradio-app/gradio@4a50a9e1831f800b999aae4fbfd23a35c930a585#subdirectory=client/python"

[gradio-pr-bot]

🦄 change detected

This Pull Request includes changes to the following packages.

Package	Version
@gradio/dropdown	patch
gradio	patch

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With the following changelog entry.

Adds a filterable parameter to gr.Dropdown that controls whether user can type to filter choices

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[dawoodkhan82]

Looks good. Maybe we should return a warning when a user tries to set allow_custom_value=True and filterable=False. Also right now when allow_custom_value=True and filterable=False is set, typing is disabled but I think filterable should be ignored and typing should be enabled.

[abidlabs]

Makes sense @dawoodkhan82, I'll make the changes

[abidlabs]

Made the changes & fixed tests -- merging

[pseudotensor]

Thanks!