Support ScaNN index

[chasingegg]

related milvus-io/milvus#2771

[mergify]

@chasingegg Please associate the related issue to the body of your Pull Request. (eg. “issue: #”)

[codecov]

Codecov Report

❗ No coverage uploaded for pull request base (main@e896528). Click here to learn what that means.
The diff coverage is n/a.

❗ Current head 9680b8e differs from pull request most recent head 6ab1e41. Consider uploading reports for the commit 6ab1e41 to get more accurate results

Additional details and impacted files

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[PwzXxm]

/lgtm
/approve

[sre-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: chasingegg, PwzXxm

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[chasingegg]

/kind improvement

[PwzXxm]

/lgtm