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GH-36247: [R] Add write_csv_dataset (#36436)

### Rationale for this change

Create a convenience wrapper around `write_dataset` for csv files. 

### What changes are included in this PR?

Adds a `write_csv_dataset()` 

### Are these changes tested?

Yes a few tests were added. 

### Are there any user-facing changes?

Yes a new function has been added. If this looks good I can add more to the docs as well. 
* Closes: #36247

Lead-authored-by: David Greiss <david.dgreiss@gmail.com>
Co-authored-by: Nic Crane <thisisnic@gmail.com>
Co-authored-by: David Greiss <dgreiss@users.noreply.github.com>
Signed-off-by: Nic Crane <thisisnic@gmail.com>