community[minor]: Add support for OVHcloud AI Endpoints Embedding (#22667)

**Description:** Add support for [OVHcloud AI
Endpoints](https://endpoints.ai.cloud.ovh.net/) Embedding models.

Inspired by:
https://gist.github.com/gmasse/e1f99339e161f4830df6be5d0095349a

Signed-off-by: Joffref <mariusjoffre@gmail.com>

libs/community/tests/unit_tests/embeddings/test_imports.py

@@ -60,6 +60,7 @@ EXPECTED_ALL = [
     "JavelinAIGatewayEmbeddings",
     "OllamaEmbeddings",
     "OracleEmbeddings",
+    "OVHCloudEmbeddings",
     "QianfanEmbeddingsEndpoint",
     "JohnSnowLabsEmbeddings",
     "VoyageEmbeddings",

libs/community/tests/unit_tests/embeddings/test_ovhcloud.py

@@ -0,0 +1,32 @@
+import pytest
+
+from langchain_community.embeddings.ovhcloud import OVHCloudEmbeddings
+
+
+def test_ovhcloud_correct_instantiation() -> None:
+    llm = OVHCloudEmbeddings(model_name="multilingual-e5-base")
+    assert isinstance(llm, OVHCloudEmbeddings)
+
+
+def test_ovhcloud_empty_model_name_should_raise_error() -> None:
+    with pytest.raises(ValueError):
+        OVHCloudEmbeddings(model_name="")
+
+
+def test_ovhcloud_empty_region_should_raise_error() -> None:
+    with pytest.raises(ValueError):
+        OVHCloudEmbeddings(model_name="multilingual-e5-base", region="")
+
+
+def test_ovhcloud_empty_access_token_should_not_raise_error() -> None:
+    llm = OVHCloudEmbeddings(
+        model_name="multilingual-e5-base", region="kepler", access_token=""
+    )
+    assert isinstance(llm, OVHCloudEmbeddings)
+
+
+def test_ovhcloud_embed_documents() -> None:
+    llm = OVHCloudEmbeddings(model_name="multilingual-e5-base")
+    docs = ["Hello", "World"]
+    output = llm.embed_documents(docs)
+    assert len(output) == len(docs)