feat: Added sync argument in Matching Engine IndexEndpoint deploy_index

[KennyStryker]

✨ Add sync argument to deploy_index method in Matching Engine IndexEndpoint

Fixes #5304 🦕

Description

This PR introduces a new sync parameter to the deploy_index method, enabling both synchronous and asynchronous deployments. By default, the method remains synchronous to preserve backward compatibility.

Changes

• Added a sync: bool = True argument to the deploy_index method.
• If sync is True, the method waits for the long-running deployment operation (LRO) to complete before returning.
• If sync is False, the method returns immediately, and the LRO completes in the background.
• Maintains all existing behavior as default.

Usage Example

# Synchronous deployment (default behavior)
endpoint.deploy_index(index=my_index, deployed_index_id="my-index-id")

# Asynchronous deployment
endpoint.deploy_index(index=my_index, deployed_index_id="my-index-id", sync=False)

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[KennyStryker]

CLA Signed.

[ericgribkoff]

Thanks for the PR! I pointed to an existing decorator in our codebase that should be used to implement the desired behavior. This change also needs a test for the sync parameter behavior, something analogous to

python-aiplatform/tests/unit/aiplatform/test_matching_engine_index_endpoint.py

Line 976 in ead5c93

def test_delete_index_endpoint(self, delete_index_endpoint_mock, sync):

[KennyStryker]

@ericgribkoff Thank you for your response. I have added the requested changes, including the updated test cases for sync.

[ericgribkoff]

LGTM, thanks for addressing the earlier comments!

[ericgribkoff]

@matthew29tang Lingyin rerouted the review to me. Changes look good and approved from Vector Search team's side, but I don't have write access to this repository.

[matthew29tang]

I will get this merged in then, thanks for the review!

[matthew29tang]

Merged in fee1e2d