milvus: Honor WithEmbedder option in AddDocuments

[HomayoonAlimohammadi]

Overview

This PR changes store.AddDocuments(...) to honor vectorestores.WithEmbedder(e) option.

PR Checklist

• [ ] Read the Contributing documentation.
• [ ] Read the Code of conduct documentation.
• [ ] Name your Pull Request title clearly, concisely, and prefixed with the name of the primarily affected package you changed according to Good commit messages (such as memory: add interfaces for X, Y or util: add whizzbang helpers).
• [ ] Check that there isn't already a PR that solves the problem the same way to avoid creating a duplicate.
• [ ] Provide a description in this PR that addresses what the PR is solving, or reference the issue that it solves (e.g. Fixes #123).
• [ ] Describes the source of new concepts.
• [ ] References existing implementations as appropriate.
• [ ] Contains test coverage for new functions.
• [ ] Passes all golangci-lint checks.

[tmc]

Thanks for your contribution. @HomayoonAlimohammadi can you rebase this to pass lint rules?

[HomayoonAlimohammadi]

Of course! Thanks for the review @tmc! Done.