[CI] Add Failure Notification to Go Mod Syncer Workflow

[leecalcote]

Current Behavior
Currently, there is no notification on failure of a Go Mod Sync workflow. The GitHub workflow silently fails (example).

Desired Behavior

1. Insert mailing list notifications on failure (and to handle special cases in which a maintainer needs to handle).
2. Email [email protected] mailing list.
3. Use the existing email action that we use with existing secrets available in our repo. MAIL_USERNAME and MAIL_PASSWORD are secrets that are available in the meshery org.

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Resources

Alternatives / Additional Context