Indicate in banner that Journalbeat has been removed in 7.16

[dedemorton]

Updating banner for 7.15 because it is the last version of Journalbeat that will be published.

[botelastic]

This pull request doesn't have a Team:<team> label.

[elasticmachine]

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• Start Time: 2021-11-24T23:23:06.399+0000

• Duration: 45 min 24 sec

• Commit: 951fdcf

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Test	Results
Failed	0
Passed	46
Skipped	4
Total	50

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