chore: Add issues write permission to release-please. (#131)

## Summary

Github made changes that default to labels not being part of the
pull-request permissions.

## How did you test this change?

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## Are there any deployment considerations?

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Author: kinyoklion

.github/workflows/release-please.yml

@@ -10,6 +10,7 @@ jobs:
         permissions:
             contents: write # Contents and pull-requests are for release-please to make releases.
             pull-requests: write
+            issues: write
         outputs:
             python-plugin-released: ${{ steps.release.outputs['sdk/@launchdarkly/observability-python--release_created'] }}
             python-plugin-tag-name: ${{ steps.release.outputs['sdk/@launchdarkly/observability-python--tag_name'] }}