Preparing for Gradle 9.0

[Eng-Fouad]

Description

Few deprecated APIs were removed in Gradle 9.0.0-RC1 and they should be replaced with the newer APIs before we can bump to Gradle 9.0 in Quarkus.

• Replace Gradle's deprecated project.exe() with newer API #48581
• Replace Gradle's deprecated project.getBuildDir() with newer API #48521
• Replace Gradle's deprecated buildIdentifier.getName() with newer API #48522
• Replace Gradle's deprecated configuration.getFiles() with newer API #48523
• Add missing @Test to grpc-multi-module-project tests #48632
• Update io.spring.dependency-management plugin version #48633
• Specify Unit as return type for Scala tests in codestarts #48649
• Fix few gradle misconfigurations related to gradle plugin tests #48650
• Remove the deprecated internal gradle API DefaultProjectDependency #48661
• Stop using detachedConfiguration().extendsFrom in ConditionalDependenciesEnabler #48551

Implementation ideas

No response

[quarkus-bot]

/cc @glefloch, @quarkusio/devtools

[Eng-Fouad]

cc @aloubyansky

[Eng-Fouad]

Related: #48598

[aloubyansky]

@Eng-Fouad the whole list is checked for the moment. Thanks for driving this one.