[Doctest] - Fixing doctest configuration_pegasus_x.py

[mukesh663]

What does this PR do?

Fixes #19487
Added (with random weights) in configuration_pegasus_x.py.
Added configuration_pegasus_x.py in documentation_tests.txt.

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• This PR fixes a typo or improves the docs (you can dismiss the other checks if that's the case).
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• Did you write any new necessary tests?

Who can review?

@ydshieh

[ydshieh]

Hi @mukesh663 There seems to be some CI issue. Could you push again with an empty commit?

You can do git commit --allow-empty then push :pray.

[ydshieh]

Nice!

[ydshieh]

Hi, @mukesh663 I haven't merge your PR yet ...but you already closed the PR and delete the branch 😢

[ydshieh]

Are you able to restore the branch ?

[mukesh663]

Are you able to restore the branch ?

@ydshieh Sorry for the mishap. I have restored the branch.

[ydshieh]

Merged, thank you again!

[HuggingFaceDocBuilderDev]

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