Add operationMetrics to WRITE

[r3stl355]

Description

Currently WriteBuilder does not collect the metrics as other operations do (e.g. delete or merge)

Use Case

Related Issue(s)

[gavinmead]

I'm interested in contributing to the project and can take a look at this one. Thanks!

[gavinmead]

After reviewing the metrics implementations for Merge and Delete it should be easy enough to replicate the same things in write. However, in write.rs the Output type for IntoFuture is a DeltaTable

impl std::future::IntoFuture for WriteBuilder {
    type Output = DeltaResult<DeltaTable>;

and to conform to the other operations and surface the metrics it would change to:

impl std::future::IntoFuture for WriteBuilder {
    type Output = DeltaResult<(DeltaTable, WriteMetrics)>;

I just wanted to surface that since this "good first issue" may touch a fair amount of files 😄

[ion-elgreco]

@gavinmead you can do the first iteration where we just record the metrics in the commit but don't return them together with the DeltaTable instance