OpenTelemetry: fix the Redis instrumenter in case of a tainted connection

[Ladicek]

The Vert.x Redis client does not always report the database instance number, because sometimes, it simply isn't known. Specifically, that occurs when the connection is tainted; for example, when a custom database is selected using the SELECT command.

In this case, the trace simply will not include the dabatase instance number.

Fixes #45167

[quarkus-bot]

/cc @brunobat (opentelemetry), @radcortez (opentelemetry)

[gsmet]

I marked it for backport to 3.17 and 3.15.

[brunobat]

Looks ok to me. Thanks @Ladicek

[quarkus-bot]

Status for workflow Quarkus CI

This is the status report for running Quarkus CI on commit 5589020.

✅ 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 Windows

📦 integration-tests/opentelemetry-quickstart

✖ io.quarkus.it.opentelemetry.OpenTelemetryDisabledTest.buildTimeDisabled - History

• Condition with Lambda expression in io.quarkus.it.opentelemetry.OpenTelemetryDisabledTest was not fulfilled within 200 milliseconds. - org.awaitility.core.ConditionTimeoutException

org.awaitility.core.ConditionTimeoutException: Condition with Lambda expression in io.quarkus.it.opentelemetry.OpenTelemetryDisabledTest was not fulfilled within 200 milliseconds.
	at org.awaitility.core.ConditionAwaiter.await(ConditionAwaiter.java:167)
	at org.awaitility.core.CallableCondition.await(CallableCondition.java:78)
	at org.awaitility.core.CallableCondition.await(CallableCondition.java:26)
	at org.awaitility.core.ConditionFactory.until(ConditionFactory.java:1006)
	at org.awaitility.core.ConditionFactory.until(ConditionFactory.java:975)
	at io.quarkus.it.opentelemetry.OpenTelemetryDisabledTest.buildTimeDisabled(OpenTelemetryDisabledTest.java:29)
	at java.base/java.lang.reflect.Method.invoke(Method.java:569)