Add Norwegian language metadata

Hello!

Well done on this model; I like the training setup a lot. This PR should add a language tag to make it easier for others to find it when looking for Norwegian embedding models.

- Tom Aarsen

README.md

@@ -1,7 +1,7 @@
 ---
 base_model: NbAiLab/nb-sbert-base
-datasets: []
-language: []
+language:
+- 'no'
 library_name: sentence-transformers
 metrics:
 - cosine_accuracy