Fix tests in REST client quickstart for the native SSL guide

[xstefank]

In Native SSL guide we start by downloading REST client and removing WireMock, but these tests use the old names of the rest-client-reactive extensions and they fail when we remove WireMock. This will fix the Native SSL guide.

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 3b9809b.

✅ The latest workflow run for the pull request has completed successfully.

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