Bump to Mutiny 2.8.0 and the Mutiny Vert.x bindings 3.18.0

[jponge]

This is a coordinated upgrade to Mutiny 2.8.0.

Noteworthy changes:

• Java 17 is now the baseline
• Fixes slow streaming in very narrow cases (e.g., the Mongo “reactive” driver)

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[quarkus-bot]

Status for workflow Quarkus CI

This is the status report for running Quarkus CI on commit 74639cb.

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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

⚙️ Gradle Tests - JDK 17 Windows

📦 integration-tests/gradle

✖ io.quarkus.gradle.devmode.MavenExclusionInExtensionDependencyDevModeTest.main - History

• Condition with Lambda expression in io.quarkus.test.devmode.util.DevModeClient was not fulfilled within 1 minutes 30 seconds. - org.awaitility.core.ConditionTimeoutException

org.awaitility.core.ConditionTimeoutException: Condition with Lambda expression in io.quarkus.test.devmode.util.DevModeClient was not fulfilled within 1 minutes  30 seconds.
	at app//org.awaitility.core.ConditionAwaiter.await(ConditionAwaiter.java:167)
	at app//org.awaitility.core.CallableCondition.await(CallableCondition.java:78)
	at app//org.awaitility.core.CallableCondition.await(CallableCondition.java:26)
	at app//org.awaitility.core.ConditionFactory.until(ConditionFactory.java:1006)
	at app//org.awaitility.core.ConditionFactory.until(ConditionFactory.java:975)
	at app//io.quarkus.test.devmode.util.DevModeClient.getHttpResponse(DevModeClient.java:164)
	at app//io.quarkus.gradle.devmode.QuarkusDevGradleTestBase.getHttpResponse(QuarkusDevGradleTestBase.java:164)