text: Title: Loading of saved model returns Error: "This BERTopic instance is not fitted yet. Call 'fit' with appropriate arguments before using this estimator."
  Body: **Edit: Nvm, I just forgot to actually save the loading into a variable...
  
  Previously saved several models using the following code:
  
  ```python3
  
  from sklearn.feature_extraction.text import CountVectorizer
  from bertopic.representation import KeyBERTInspired, PartOfSpeech, MaximalMarginalRelevance
  
  main_representation_model = KeyBERTInspired()
  aspect_representation_model1 = PartOfSpeech("en_core_web_sm")
  aspect_representation_model2 = [KeyBERTInspired(top_n_words=30), MaximalMarginalRelevance(diversity=.5)]
  
  representation_model = {
     "Main": main_representation_model,
     "Aspect1":  aspect_representation_model1,
     "Aspect2":  aspect_representation_model2 
  }
  
  vectorizer_model = CountVectorizer(min_df=5, stop_words = 'english')
  topic_mdl = BERTopic(nr_topics = 'auto', vectorizer_model = vectorizer_model,
                        representation_model = representation_model, verbose=True)
  
  apps = ['Assetto Corsa', 'Assetto Corsa Competizione', 'Beat Saber', 'CarX Drift Racing Online', 'DCS World Steam Edition', 'DEVOUR', 'Golf It!', 'Gorilla Tag', 'Hand Simulator', 'Microsoft Flight Simulator 40th Anniversary Edition',
         'No_Mans_Sky', 'Paint the Town Red', 'Pavlov VR', 'Phasmophobia', 'Rec Room', 'STAR WARS™: Squadrons', 'Tabletop Simulator', 'VRChat', 'VTOL VR', 'War Thunder']
  
  app = apps[5]
  docs = dfs_reviews[app]
  topic, ini_probs = topic_mdl.fit_transform(docs)
  topics_info = get_topic_stats(topic_mdl)
  
  # Saving model
  topic_mdl.save(f'./topic_models/{app}', serialization='safetensors', save_ctfidf=True)
  ```
  
  Then when I tried loading it and visualise it using the barplot:
  
  ```python3
  topic_mdl.load(f'./topic_models/{app[3]}')
  topic_mdl.visualize_barchart(top_n_topics = 16, n_words = 10)
  ```
  
  it gives the following error:
  
  ```
  {
  	"name": "ValueError",
  	"message": "This BERTopic instance is not fitted yet. Call 'fit' with appropriate arguments before using this estimator.",
  	"stack": "---------------------------------------------------------------------------
  ValueError                                Traceback (most recent call last)
  Cell In[25], line 5
        1 app = ['Assetto Corsa', 'Assetto Corsa Competizione', 'Beat Saber', 'CarX Drift Racing Online', 'DCS World Steam Edition', 'DEVOUR', 'Golf It!', 'Gorilla Tag', 'Hand Simulator', 'Microsoft Flight Simulator 40th Anniversary Edition',
        2        'No_Mans_Sky', 'Paint the Town Red', 'Pavlov VR', 'Phasmophobia', 'Rec Room', 'STAR WARS™: Squadrons', 'Tabletop Simulator', 'VRChat', 'VTOL VR', 'War Thunder']
        4 topic_mdl.load(f'./topic_models/{app[3]}')
  ----> 5 topic_mdl.get_topic_info()
  
  File ~/Uni Codes/Thesis/Web-Scraper/env/lib/python3.10/site-packages/bertopic/_bertopic.py:1514, in BERTopic.get_topic_info(self, topic)
     1499 def get_topic_info(self, topic: int = None) -> pd.DataFrame:
     1500     \"\"\" Get information about each topic including its ID, frequency, and name.
     1501 
     1502     Arguments:
     (...)
     1512     ```
     1513     \"\"\"
  -> 1514     check_is_fitted(self)
     1516     info = pd.DataFrame(self.topic_sizes_.items(), columns=[\"Topic\", \"Count\"]).sort_values(\"Topic\")
     1517     info[\"Name\"] = info.Topic.map(self.topic_labels_)
  
  File ~/Uni Codes/Thesis/Web-Scraper/env/lib/python3.10/site-packages/bertopic/_utils.py:76, in check_is_fitted(topic_model)
       72 msg = (\"This %(name)s instance is not fitted yet. Call 'fit' with \"
       73        \"appropriate arguments before using this estimator.\")
       75 if topic_model.topics_ is None:
  ---> 76     raise ValueError(msg % {'name': type(topic_model).__name__})
  
  ValueError: This BERTopic instance is not fitted yet. Call 'fit' with appropriate arguments before using this estimator."
  }
  ```
  
  I can't seem to find anything related to this online. I read that I shouldn't be fitting it again as that would defeat the whole point of saving it in the first place from this issue #1584 .
  
  Any help would be greatly appreciated.
  Thank you