OTEL persistence context deadline (temporalio#7208)

## What changed?
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Added "persistence.deadline" attributes to OTEL persistence span.

## Why?
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Add more details for debugging.

## How did you test it?
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test? Checked in staging env? -->

## Potential risks
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change to production? -->

## Documentation
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new behavior is added, have you described that in `docs/`? -->

## Is hotfix candidate?
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Author: stephanos