[Doctests] add `configuration_blenderbot_small.py`
Author: grgkaran03
Pull request: yes

# What does this PR do?
add `configuration_blenderbot_small.py` for doctests, addressing issue #19487. Please review @ydshieh.

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Comments:
@ydshieh how can I rectify the failing check? Did not occur before in any other PRs.

_The documentation is not available anymore as the PR was closed or merged._

> @ydshieh how can I rectify the failing check? Did not occur before in any other PRs.

That test is somehow flaky. I re-ran it and now it pass.