multilingual e5 small CLI failure

[isaac-chung]

Running this (added as test case in the branch e5-model-test:

mteb run -m intfloat/multilingual-e5-small -t BornholmBitextMining --verbosity 3 --output_folder tests/results/test_model --model_revision e4ce9877abf3edfe10b0d82785e83bdcb973e22e

gives

...
  File "/home/ubuntu/isaac/work/mteb/mteb/evaluation/evaluators/model_encode.py", line 26, in model_encode
    embeddings = model.encode(sentences, **kwargs)
                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/ubuntu/isaac/work/mteb/mteb/models/e5_models.py", line 134, in encode
    return self.encode_queries(sentences, batch_size=batch_size, **kwargs)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/ubuntu/isaac/work/mteb/mteb/models/e5_models.py", line 138, in encode_queries
    emb = self.mdl.encode(sentences, batch_size=batch_size, **kwargs)
          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/ubuntu/miniconda3/lib/python3.11/site-packages/sentence_transformers/SentenceTransformer.py", line 451, in encode
    raise ValueError(
ValueError: Prompt name 'BornholmBitextMining' not found in the configured prompts dictionary with keys [].

Seems to be related to the changes introduced in #888