Update daily EA build Slack status to handle when GA builds are published

[andrew-m-leonard]

• If the latest upstream tag is a GA build then don't expect an ea-beta build for it
• Also if a version has published a GA tag, then don't expect the ea-beta releases to be built for all the latest tags, as sometimes more than one build tag is published on a GA release

[github-actions]

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[steelhead31]

lgtm