community[patch]: standardize chat init args (#20844)
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community:perplexity[patch]: standardize init args
updated pplx_api_key and request_timeout so that aliased to api_key, and
timeout respectively. Added test that both continue to set the same
underlying attributes.
Related to
[20085](https://github.com/langchain-ai/langchain/issues/20085)
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Co-authored-by: Bagatur <22008038+baskaryan@users.noreply.github.com>
