Adds name + status + message to Slack notification

[blozano824]

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Description

Fixes #2706 by taking the existing message displayed using Block Kit and including it in the text to provide a more detailed Slack notification.

Type of change

• New feature (non-breaking change which adds functionality)

Checklist

• My code follows the style guidelines of this project
• I ran ESLint and other linters for modified files
• I have performed a self-review of my own code and tested it
• I have commented my code, particularly in hard-to-understand areas
  (including JSDoc for methods)
• My changes generate no new warnings
• My code needed automated testing. I have added them (this is optional task)

Screenshots (if any)

Slack Notification When Up

Slack Notification When Down

Slack Messages In Channel