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GH-41993 [Go] IPC writer shift voffsets when offsets array does not start from zero (#43176)



### Rationale for this change

It should be valid to specify offset buffers that do not start from zero. This particularly important for when multiple arrays share a single value buffer.

### What changes are included in this PR?

- Add condition to shift offsets buffer when it does not start from zero
- Test to reproduce failure and then validate fix

### Are these changes tested?

Yes

### Are there any user-facing changes?

Variable-length binary arrays that share a value buffer will not result in errors.

* GitHub Issue: #41993

Authored-by: Joel Lubinitsky <joellubi@gmail.com>
Signed-off-by: Joel Lubinitsky <joellubi@gmail.com>