Updates to reflect current extension names and configuration roots

[rolfedh]

Updates to ensure the conditionals and content reflect the changes described in RESTEasy Reactive extensions renamed to Quarkus REST

[quarkus-bot]

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[quarkus-bot]

Status for workflow Quarkus Documentation CI

This is the status report for running Quarkus Documentation CI on commit 9f55339.

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It should be safe to merge provided you have a look at the other checks in the summary.

[github-actions]

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[gsmet]

Good catch, thanks!