Hibernate: Prefix %prod in multi tenant schema example

[lucamolteni]

See quarkusio/quarkus#45715 (comment)

Check list:

Your pull request:

• targets the development branch
• uses the 999-SNAPSHOT version of Quarkus
• has tests (mvn clean test)
• works in native (mvn clean package -Pnative)
• has integration/native tests (mvn clean verify -Pnative)
• makes sure the associated guide must not be updated
• links the guide update pull request (if needed)
• updates or creates the README.md file (with build and run instructions)
• for new quickstart, is located in the directory component-quickstart
• for new quickstart, is added to the root pom.xml and README.md

[quarkus-bot]

Status for workflow Pull Request Build - development

This is the status report for running Pull Request Build - development on commit 3aa33db.

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