fix: Fastembed - Change default Sparse model as the used one is deprecated due to a typo

[paulmartrencharpro]

The name of the model prithvida/Splade_PP_en_v1 has a typo and is being replaced by prithivida/Splade_PP_en_v1? There's a Deprecation warning about it.
I changed it everywhere in the class & the tests

How did you test it?

Unit tests

Notes for the reviewer

This is changing the behavior if users have not set the model name when creating a FastembedSparseDocumentEmbedder() or FastembedSparseTextEmbedder() as it is the default model in our implementation.

The code in the init on the fastembed side has this code (https://github.com/qdrant/fastembed/blob/main/fastembed/sparse/sparse_text_embedding.py#L58) that raises the deprecation and changes the model.
if model_name == "prithvida/Splade_PP_en_v1":
warnings.warn(
"The right spelling is prithivida/Splade_PP_en_v1. "
"Support of this name will be removed soon, please fix the model_name",
DeprecationWarning,
stacklevel=2,
)
model_name = "prithivida/Splade_PP_en_v1"

Checklist

• I have read the contributors guidelines and the code of conduct
• I have updated the related issue with new insights and changes
• I added unit tests and updated the docstrings
• I've used one of the conventional commit types for my PR title: fix:, feat:, build:, chore:, ci:, docs:, style:, refactor:, perf:, test:.

[anakin87]

Thanks for the fix!