Allow buffering the REST Client Response when on a blocking thread

[geoand]

• Closes: Client ResponseExceptionMapper cannot read Response Entity Twice after migration to 3.25.0 #49379
• Closes: [3.25.0] - REST-Client throws "BlockingNotAllowedException" on method that returns "Response"-object #49280

[quarkus-bot]

Status for workflow Quarkus CI

This is the status report for running Quarkus CI on commit 4478d60.

✅ 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

⚙️ Gradle Tests - JDK 17

📦 integration-tests/gradle

❌ io.quarkus.gradle.BuildConfigurationTest.buildNoOverride - History

• Multiple Failures (1 failure) -- failure 1 -- [sub project 'without-configuration', package type 'fast-jar'] Expecting path: - org.assertj.core.error.AssertJMultipleFailuresError

org.assertj.core.error.AssertJMultipleFailuresError: 

Multiple Failures (1 failure)
-- failure 1 --
[sub project 'without-configuration', package type 'fast-jar'] 
Expecting path:
  /home/runner/_work/quarkus/quarkus/integration-tests/gradle/target/classes/build-configuration/without-configuration/build/quarkus-app/quarkus-run.jar
to exist (symbolic links were followed).

• Multiple Failures (1 failure) -- failure 1 -- [sub project 'without-configuration', package type 'fast-jar'] Expecting path: - org.assertj.core.error.AssertJMultipleFailuresError

org.assertj.core.error.AssertJMultipleFailuresError: 

Multiple Failures (1 failure)
-- failure 1 --
[sub project 'without-configuration', package type 'fast-jar'] 
Expecting path:
  /home/runner/_work/quarkus/quarkus/integration-tests/gradle/target/classes/build-configuration/without-configuration/build/quarkus-app/quarkus-run.jar
to exist (symbolic links were followed).

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⚙️ Gradle Tests - JDK 17 Windows

📦 integration-tests/gradle

❌ io.quarkus.gradle.BuildConfigurationTest.buildFastJarOverride - History

• Multiple Failures (1 failure) -- failure 1 -- [sub project 'without-configuration', package type 'fast-jar'] Expecting path: - org.assertj.core.error.AssertJMultipleFailuresError

org.assertj.core.error.AssertJMultipleFailuresError: 

Multiple Failures (1 failure)
-- failure 1 --
[sub project 'without-configuration', package type 'fast-jar'] 
Expecting path:
  D:\a\quarkus\quarkus\integration-tests\gradle\target\classes\build-configuration\without-configuration\build\quarkus-app\quarkus-run.jar
to exist (symbolic links were followed).

[geoand]

@cescoffier mind reviewing this one? It's pretty important in fixing a recurring issue plenty of users have mentioned.