Remove obsolete warning about dev mode in lambda quickstarts

[holly-cummins]

Our lambda quickstarts have a big warning saying dev mode doesn't work. (See https://github.com/dagrammy/lambda-test-reproducer?tab=readme-ov-file for an example).

This warning is obsolete.

https://quarkus.io/guides/aws-lambda says

Quarkus’s integration with lambdas also supports Quarkus’s Live Coding development cycle. You can bring up your Quarkus lambda project in dev or test mode and code on your project live.

https://quarkus.io/guides/funqy-knative-events says

Funqy Knative Events support dev mode and unit testing using RestAssured.

I raised a separate PR (#48713) for the bad guide link in the quickstart readme.

[quarkus-bot]

Status for workflow Quarkus CI

This is the status report for running Quarkus CI on commit 4a68467.

✅ 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 Integration Tests - JDK 21

📦 integration-tests/opentelemetry-grpc-only

✖ io.quarkus.it.opentelemetry.grpc.HelloGrpcClientTest.testHello - History

• java.lang.RuntimeException: Failed to start quarkus - java.lang.RuntimeException

java.lang.RuntimeException: java.lang.RuntimeException: Failed to start quarkus
	at io.quarkus.test.junit.QuarkusTestExtension.throwBootFailureException(QuarkusTestExtension.java:668)
	at io.quarkus.test.junit.QuarkusTestExtension.interceptTestClassConstructor(QuarkusTestExtension.java:763)
	at java.base/java.util.Optional.orElseGet(Optional.java:364)
	at java.base/java.util.ArrayList.forEach(ArrayList.java:1596)
	at java.base/java.util.ArrayList.forEach(ArrayList.java:1596)
Caused by: java.lang.RuntimeException: Failed to start quarkus
	at io.quarkus.runner.ApplicationImpl.doStart(Unknown Source)