Use the bootRun javaLauncher in fork task

Verified in a new Spring initializer project (plus springdoc and plugin)
for both Java and Kotlin.

For Java, choose Java 24 as toolchain version in build.gradle but configure Gradle JVM
to Java 23 or earlier.

For Kotlin, use Java 21 as bytecode version, but for illustrative purposes, downgrade
Gradle JVM to Java 19 for example.

LinkageError, java.lang.UnsupportedClassVersionError occurs in forkedSpringBootRun task
in both cases (but with different encountered versus supported class file versions)

Author: tjog

src/main/kotlin/org/springdoc/openapi/gradle/plugin/OpenApiGradlePlugin.kt

@@ -110,6 +110,11 @@ open class OpenApiGradlePlugin : Plugin<Project> {
 				?: bootRun.jvmArgs
 			environment = customBootRun.environment.orNull?.takeIf { it.isNotEmpty() }
 				?: bootRun.environment
+
+			// Respect javaLauncher configured for bootRun, so Gradle JVM version
+			// (which may differ) is not used.
+			javaLauncher.set(bootRun.javaLauncher)
+
 			if (Jvm.current().toString().startsWith("1.8")) {
 				killDescendants = false
 			}