Add support for SqlConnectionOverrides for OpenAsync() API

[cheenamalhotra]

As the name suggests, introduces new API:

public Task SqlConnection.OpenAsync(SqlConnectionOverrides overrides, CancellationToken cancellationToken);

Previously, we skipped addiing overrides to OpenAsync in PR #463 due to no transient fault handling, but with recent PR #1983 we now enable transient fault handling by default for OpenAsync() too.

To support fail fast behavior in OpenAsync(), we need to allow passing SqlConnectionOverrides in OpenAsync() too.

Additional context:
dotnet/efcore#33399
#29

[mdaigle]

Based on my current understanding, the existing default is to not apply transient fault handling for OpenAsync. This changes the default to applying transient fault handling.

It seems like there are two options if we want to make a change now:

1. modify this change to retain the current default behavior
2. do this change, but only apply it on a new (major?) version

However, given what we've learned about the slow, serial nature of OpenAsync, part of me feels like we should wait to do this change until general async performance is improved.

I would advocate for waiting.

[DavoudEshtehari]

@cheenamalhotra Could you wrap this up for the preview 1 with the outstanding comments? Generally, this looks good to me and I'd rather not pushing it to the next preview.

[cheenamalhotra]

/azp run

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