Fix GithubReleaseV1 crash when commit includes discussion id

[edvilme]

Context

Describe the context or motivation for this PR. Include links to any related Azure DevOps Work Items or GitHub issues.
📌 How to link to ADO Work Items
When running pipeline https://devdiv.visualstudio.com/DevDiv/_build/results?buildId=13386513&view=logs&j=739bb7ec-7296-5b40-7dff-ee3297bfdaa4&t=fd6eb289-d702-51fc-9ee6-4f19a6a112bf for releasing, one of the commits mentioned a GitHub Discussion item, which was not found by the tool, causing it to not generate release notes.

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Task Name

Name of the updated or newly created pipeline task.
GithubReleaseV1

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Description

Summarize the changes made in this PR clearly and concisely.
The issueOrPullRequest GraphQL return null for Discussion items, causing a TypeError when accessing .title or .state on null entries. Thus, crashing the step and not generating the release notes.

Added null guards to gracefully skip Discussion references instead of crashing.

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Risk Assessment (Low / Medium / High)

Assess the level of risk and provide reasoning (e.g., scope, impact, backward compatibility).
Low, adds null checks

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Change Behind Feature Flag (Yes / No)

Can this change be behind feature flag, if not why?
Yes

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Tech Design / Approach

• Design has been written and reviewed.
• Any architectural decisions, trade-offs, and alternatives are captured.

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Documentation Changes Required (Yes/No)

Indicate whether related documentation needs to be updated.

• User guides, API specs, system diagrams, or runbooks are updated.

Mention that Github Discussions are not included.

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Unit Tests Added or Updated (Yes / No)

Indicate whether unit tests were added or modified to reflect these changes.
N/A

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Additional Testing Performed

List all other tests performed (manual or automated, including integration, regression, scenario tests, etc.).
N/A

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Logging Added/Updated (Yes/No)

• Appropriate log statements are added with meaningful messages.
• Logging does not expose sensitive data.
• Log levels are used correctly (e.g., info, warn, error).

N/A

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Telemetry Added/Updated (Yes/No)

• Custom telemetry (e.g., counters, timers, error tracking) is added as needed.
• Events are tagged with proper metadata for filtering and analysis.
• Telemetry is validated in staging or test environments.

N/A

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Rollback Scenario and Process (Yes/No)

• Rollback plan is documented.

N/A

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Dependency Impact Assessed and Regression Tested (Yes/No)

• All impacted internal modules, APIs, services, and third-party libraries are analyzed.
• Results are reviewed and confirmed to not break existing functionality.

N/A

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Checklist

• Related issue linked (if applicable)
• Task version was bumped — see versioning guide
• Verified the task behaves as expected

[edvilme]

Fixes #21870

[edvilme]

Related to #21112