Bump slackapi/slack-github-action from v3.0.3 to v3.0.5 in /.github/workflows

[UltralyticsAssistant]

Bump slackapi/slack-github-action from v3.0.3 to v3.0.5 in /.github/workflows

This PR updates GitHub Actions references in this repository.

Examples:

• Branch: actions/checkout@main stays on @main
• Major tag: actions/checkout@v4 updates to @v5
• Specific tag: astral-sh/setup-uv@v0.5.0 updates to @v0.9.4
• SHA pinned: actions/checkout@<sha> # v4.1.0 updates to the latest release SHA and tag comment

_{Made with ❤️ by Ultralytics Actions}

🛠️ PR Summary

_{Made with ❤️ by Ultralytics Actions}

🌟 Summary

Updated the GitHub Actions Slack notification integration to a newer patch release. 🔔

📊 Key Changes

• Upgraded slackapi/slack-github-action from v3.0.3 to v3.0.5.
• Applied the update to both successful release notifications and failure alerts.
• Kept the existing webhook configuration and notification messages unchanged.

🎯 Purpose & Impact

• Improves reliability and compatibility of Slack notifications with the latest action fixes. ✅
• Ensures release success and failure messages continue using the maintained action version.
• No expected changes to the publishing workflow or user-facing documentation behavior.