docs: typo with Embedder service (#269)

Hello ,

This PR is a suggestion to change the name of embedding providers
variables and classes .

If you accept my suggestion , the PR to adopt this into the bundle is
almost ready .

Author: Iyadhfaleh

README.md

@@ -350,7 +350,7 @@ $eventDispatcher->addListener(ToolCallsExecuted::class, function (ToolCallsExecu
 LLM Chain supports document embedding and similarity search using vector stores like ChromaDB, Azure AI Search, MongoDB
 Atlas Search, or Pinecone.
 
-For populating a vector store, LLM Chain provides the service `DocumentEmbedder`, which requires an instance of an
+For populating a vector store, LLM Chain provides the service `Embedder`, which requires an instance of an
 `EmbeddingsModel` and one of `StoreInterface`, and works with a collection of `Document` objects as input:
 
 ```php