Fix pipeline id which defaults to __default__ pipeline

Description

Kedro-Viz URL points to __default__ pid even if there is no pipeline with the id __default__. This breaks the UI and shows as below -

Context

I have a kedro project which returns 1 pipeline as below -

generic_pipeline = gn.create_pipeline()

    return {
        "Generic": generic_pipeline
    }

The dropdown in the pipeline selector shows Generic but the URL pid points to __default__. This partially breaks Kedro-Viz

NOTE: This is working on Kedro-Viz < 9.0.0. This might be due to the stateful URL. However when I tried to re-produce this on latest Kedro-Viz, it started working. I would request anyone else (cc: @jitu5 ) to test this as I was unable to re-produce and I do not see any default pid on Frontend. Please feel free to close the ticket if everything looks good.

Steps to Reproduce

Remove __default__ pipeline from demo_project
Run kedro viz run
You will see the message Oops, this URL isn't valid

Expected Result

Kedro-Viz should show the pipeline which is selected in the dropdown
The URL should point to the selected pipeline id in case there is no __default__ pipeline

Actual Result

You will see the message Oops, this URL isn't valid

Your Environment

Include as many relevant details as possible about the environment you experienced the bug in:

Web browser system and version: Chrome
Operating system and version: mac
NodeJS version used (if relevant):
Kedro version used (if relevant):
Python version used (if relevant):

Checklist

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kedro-org / kedro-viz