feat(module): bump notification module and replace accounts id var

[shanilhirani]

As per title,

this updates the notification module to 2.0 and replaces the variable

[github-actions]

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Working Directory: .
Pusher: @shanilhirani, Action: pull_request
Workflow Run Link: https://github.com/appvia/terraform-aws-alarm-baseline/actions/runs/12793352346