Include instrumentation scope

[rads-1996]

Description

Fixes - #45914. Adds the logger name to Message, Exception and Events telemetry.

All SDK Contribution checklist:

• The pull request does not introduce [breaking changes]
• CHANGELOG is updated for new features, bug fixes or other significant changes.
• I have read the contribution guidelines.

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• Title of the pull request is clear and informative.
• There are a small number of commits, each of which have an informative message. This means that previously merged commits do not appear in the history of the PR. For more information on cleaning up the commits in your PR, see this page.

Testing Guidelines

• Pull request includes test coverage for the included changes.

[Copilot]

Pull request overview

Adds OpenTelemetry InstrumentationScope.name (logger name) into Azure Monitor log telemetry custom dimensions so that Message, Exception, and Event envelopes include source logger information (fixing #45914).

Changes:

• Populate logger_name in log envelope properties from readable_log_record.instrumentation_scope.name.
• Update log exporter tests to include assertions for logger_name on Message/Exception scenarios and adjust test instrumentation scope names.
• Document the new behavior in the package changelog.

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 2 comments.

File	Description
sdk/monitor/azure-monitor-opentelemetry-exporter/azure/monitor/opentelemetry/exporter/export/logs/_exporter.py	Adds instrumentation scope name into log envelope custom properties.
sdk/monitor/azure-monitor-opentelemetry-exporter/tests/logs/test_logs.py	Updates fixtures and adds assertions related to exported logger name.
sdk/monitor/azure-monitor-opentelemetry-exporter/CHANGELOG.md	Notes the new feature in the unreleased section.