Update accessibility-alt-text-bot.yml

[kendallgassner]

Update our accessibility-alt-text-bot to get:

• delete alt-text-bot comment when there are no longer errors
• edit existing alt-text-bot comments when the error message changes
• more descriptive alt-text-bot message

Risk Assessment

• Low risk the change is small, highly observable, and easily rolled back.
• Medium risk changes that are isolated, reduced in scope or could impact few users. The change will not impact library availability.
• High risk changes are those that could impact customers and SLOs, low or no test coverage, low observability, or slow to rollback.

[changeset-bot]

⚠️ No Changeset found

Latest commit: 411c52e

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