Python: added embedding dimensions support (#6111)

### Motivation and Context

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### Description

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added embedding dimensions support (issue:
#5882)

### Contribution Checklist

<!-- Before submitting this PR, please make sure: -->

- [] The code builds clean without any errors or warnings
- [] The PR follows the [SK Contribution
Guidelines](https://github.com/microsoft/semantic-kernel/blob/main/CONTRIBUTING.md)
and the [pre-submission formatting
script](https://github.com/microsoft/semantic-kernel/blob/main/CONTRIBUTING.md#development-scripts)
raises no violations
- [] All unit tests pass, and I have added new tests where possible
- [] I didn't break anyone 😄

---------

Co-authored-by: Sin Yu Bonnie Ho <[email protected]>
Co-authored-by: Eduard van Valkenburg <[email protected]>

python/semantic_kernel/connectors/ai/open_ai/prompt_execution_settings/open_ai_prompt_execution_settings.py

@@ -82,3 +82,4 @@ class OpenAIEmbeddingPromptExecutionSettings(PromptExecutionSettings):
     extra_query: Optional[Dict] = None
     extra_body: Optional[Dict] = None
     timeout: Optional[float] = None
+    dimensions: Optional[int] = Field(None, gt=0, le=3072)

python/tests/unit/connectors/open_ai/services/test_azure_text_embedding.py

@@ -130,6 +130,7 @@ async def test_azure_text_embedding_calls_with_parameters(mock_create) -> None:
     api_key = "test_api_key"
     api_version = "2023-03-15-preview"
     texts = ["hello world", "goodbye world"]
+    embedding_dimensions = 1536
 
     azure_text_embedding = AzureTextEmbedding(
         deployment_name=deployment_name,
@@ -138,11 +139,12 @@ async def test_azure_text_embedding_calls_with_parameters(mock_create) -> None:
         api_version=api_version,
     )
 
-    await azure_text_embedding.generate_embeddings(texts)
+    await azure_text_embedding.generate_embeddings(texts, dimensions=embedding_dimensions)
 
     mock_create.assert_awaited_once_with(
         input=texts,
         model=deployment_name,
+        dimensions=embedding_dimensions,
     )
 
 

python/tests/unit/connectors/open_ai/services/test_openai_text_embedding.py

@@ -0,0 +1,30 @@
+# Copyright (c) Microsoft. All rights reserved.
+
+from unittest.mock import AsyncMock, patch
+
+import pytest
+from openai.resources.embeddings import AsyncEmbeddings
+
+from semantic_kernel.connectors.ai.open_ai.services.open_ai_text_embedding import OpenAITextEmbedding
+
+
+@pytest.mark.asyncio
+@patch.object(AsyncEmbeddings, "create", new_callable=AsyncMock)
+async def test_openai_text_embedding_calls_with_parameters(mock_create) -> None:
+    ai_model_id = "test_model_id"
+    api_key = "test_api_key"
+    texts = ["hello world", "goodbye world"]
+    embedding_dimensions = 1536
+
+    openai_text_embedding = OpenAITextEmbedding(
+        ai_model_id=ai_model_id,
+        api_key=api_key,
+    )
+
+    await openai_text_embedding.generate_embeddings(texts, dimensions=embedding_dimensions)
+
+    mock_create.assert_awaited_once_with(
+        input=texts,
+        model=ai_model_id,
+        dimensions=embedding_dimensions,
+    )