Update OIDC MTLS test to use generated certificates

[sberyozkin]

I'm using the Maven plugin, as opposed to the JUnit extension, because I plan to use the same certificates for the OIDC MTLs authentication, when they have to be available early.
There is another PR but I'd like to make the next one backportable to 3.15

[quarkus-bot]

Status for workflow Quarkus CI

This is the status report for running Quarkus CI on commit f8b8736.

✅ 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.

You can consult the Develocity build scans.

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Flaky tests - Develocity

⚙️ JVM Tests - JDK 17

📦 extensions/smallrye-reactive-messaging/deployment

✖ io.quarkus.smallrye.reactivemessaging.hotreload.ConnectorChangeTest.testUpdatingConnector - History

• Expecting actual: ["-4","-5","-6","-7","-8","-9","-10","-11"] to start with: ["-3", "-4", "-5", "-6"] - java.lang.AssertionError

java.lang.AssertionError: 

Expecting actual:
  ["-4","-5","-6","-7","-8","-9","-10","-11"]
to start with:
  ["-3", "-4", "-5", "-6"]

	at io.quarkus.smallrye.reactivemessaging.hotreload.ConnectorChangeTest.testUpdatingConnector(ConnectorChangeTest.java:36)