Fix lint errors

integrations/fastembed/src/haystack_integrations/components/rankers/fastembed/ranker.py

@@ -10,24 +10,24 @@
 @component
 class FastembedRanker:
     """
-    Ranks Documents based on their similarity to the query using [Fastembed models](https://qdrant.github.io/fastembed/examples/Supported_Models/).
+     Ranks Documents based on their similarity to the query using [Fastembed models](https://qdrant.github.io/fastembed/examples/Supported_Models/).
 
-    Documents are indexed from most to least semantically relevant to the query.
+     Documents are indexed from most to least semantically relevant to the query.
 
-    Usage example:
-    ```python
-    from haystack import Document
-    from haystack_integrations.components.rankers.fastembed import FastembedRanker
+     Usage example:
+     ```python
+     from haystack import Document
+     from haystack_integrations.components.rankers.fastembed import FastembedRanker
 
-    ranker = FastembedRanker(model_name="Xenova/ms-marco-MiniLM-L-6-v2", top_k=2)
+     ranker = FastembedRanker(model_name="Xenova/ms-marco-MiniLM-L-6-v2", top_k=2)
 
-    docs = [Document(content="Paris"), Document(content="Berlin")]
-    query = "What is the capital of germany?"
-    output = ranker.run(query=query, documents=docs)
-   print(output["documents"][0].content)
-   
-   # Berlin
-    ```
+     docs = [Document(content="Paris"), Document(content="Berlin")]
+     query = "What is the capital of germany?"
+     output = ranker.run(query=query, documents=docs)
+    print(output["documents"][0].content)
+
+    # Berlin
+     ```
     """
 
     def __init__(
@@ -63,8 +63,9 @@ def __init__(
             to the Document content.
         """
         if top_k <= 0:
-            raise ValueError(f"top_k must be > 0, but got {top_k}")
-
+            msg = f"top_k must be > 0, but got {top_k}"
+            raise ValueError(msg)
+
         self.model_name = model_name
         self.top_k = top_k
         self.cache_dir = cache_dir