Update docs/architecture.md (#2)

- Update docs/architecture.md (f791133a63ad3dcc1bbbd91e2397fb5689d8d571)


Co-authored-by: Jessica López <jessicalopez@users.noreply.huggingface.co>

docs/architecture.md

@@ -44,7 +44,7 @@ Mars 5 follows a two-stage AR-NAR design according to the diagram on the main pa
 
 #### AR component
 
-The AR model follows a Mistral-style encoder-only transformer model to predict Encodec L0 codes (the lowest/most coarse level quantization codes).
+The AR model follows a Mistral-style decoder-only transformer model to predict Encodec L0 codes (the lowest/most coarse level quantization codes).
 Overall, the AR and NAR model is going to predict all 8 codebook entries of the Encodec 6kbps codec. 
 The AR model design is given below: